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cppcheck/test/testcondition.cpp

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/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2019 Cppcheck team.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "checkcondition.h"
#include "library.h"
#include "settings.h"
#include "testsuite.h"
#include "tokenize.h"
#include <simplecpp.h>
#include <tinyxml2.h>
#include <map>
#include <vector>
class TestCondition : public TestFixture {
public:
TestCondition() : TestFixture("TestCondition") {
}
private:
Settings settings0;
Settings settings1;
void run() OVERRIDE {
LOAD_LIB_2(settings0.library, "qt.cfg");
LOAD_LIB_2(settings0.library, "std.cfg");
settings0.addEnabled("style");
settings0.addEnabled("warning");
const char cfg[] = "<?xml version=\"1.0\"?>\n"
"<def>\n"
" <function name=\"bar\"> <pure/> </function>\n"
"</def>";
tinyxml2::XMLDocument xmldoc;
xmldoc.Parse(cfg, sizeof(cfg));
settings1.addEnabled("style");
settings1.addEnabled("warning");
settings1.library.load(xmldoc);
TEST_CASE(assignAndCompare); // assignment and comparison don't match
TEST_CASE(mismatchingBitAnd); // overlapping bitmasks
TEST_CASE(comparison); // CheckCondition::comparison test cases
TEST_CASE(multicompare); // mismatching comparisons
TEST_CASE(overlappingElseIfCondition); // overlapping conditions in if and else-if
TEST_CASE(oppositeElseIfCondition); // opposite conditions in if and else-if
TEST_CASE(checkBadBitmaskCheck);
TEST_CASE(incorrectLogicOperator1);
TEST_CASE(incorrectLogicOperator2);
TEST_CASE(incorrectLogicOperator3);
TEST_CASE(incorrectLogicOperator4);
TEST_CASE(incorrectLogicOperator5); // complex expressions
TEST_CASE(incorrectLogicOperator6); // char literals
TEST_CASE(incorrectLogicOperator7); // opposite expressions: (expr || !expr)
TEST_CASE(incorrectLogicOperator8); // !
TEST_CASE(incorrectLogicOperator9);
TEST_CASE(incorrectLogicOperator10); // enum
TEST_CASE(incorrectLogicOperator11);
TEST_CASE(incorrectLogicOperator12);
TEST_CASE(incorrectLogicOperator13);
TEST_CASE(incorrectLogicOperator14);
TEST_CASE(secondAlwaysTrueFalseWhenFirstTrueError);
TEST_CASE(incorrectLogicOp_condSwapping);
TEST_CASE(testBug5895);
TEST_CASE(testBug5309);
TEST_CASE(modulo);
TEST_CASE(oppositeInnerCondition);
TEST_CASE(oppositeInnerConditionPointers);
TEST_CASE(oppositeInnerConditionClass);
TEST_CASE(oppositeInnerConditionUndeclaredVariable);
TEST_CASE(oppositeInnerConditionAlias);
TEST_CASE(oppositeInnerCondition2);
TEST_CASE(oppositeInnerCondition3);
TEST_CASE(oppositeInnerConditionAnd);
TEST_CASE(oppositeInnerConditionEmpty);
TEST_CASE(oppositeInnerConditionFollowVar);
TEST_CASE(identicalInnerCondition);
TEST_CASE(identicalConditionAfterEarlyExit);
TEST_CASE(innerConditionModified);
TEST_CASE(clarifyCondition1); // if (a = b() < 0)
TEST_CASE(clarifyCondition2); // if (a & b == c)
TEST_CASE(clarifyCondition3); // if (! a & b)
TEST_CASE(clarifyCondition4); // ticket #3110
TEST_CASE(clarifyCondition5); // #3609 CWinTraits<WS_CHILD|WS_VISIBLE>..
TEST_CASE(clarifyCondition6); // #3818
TEST_CASE(clarifyCondition7);
TEST_CASE(clarifyCondition8);
TEST_CASE(alwaysTrue);
TEST_CASE(multiConditionAlwaysTrue);
TEST_CASE(duplicateCondition);
TEST_CASE(checkInvalidTestForOverflow);
TEST_CASE(checkConditionIsAlwaysTrueOrFalseInsideIfWhile);
TEST_CASE(alwaysTrueFalseInLogicalOperators);
TEST_CASE(pointerAdditionResultNotNull);
TEST_CASE(duplicateConditionalAssign);
}
void check(const char code[], const char* filename = "test.cpp", bool inconclusive = false) {
// Clear the error buffer..
errout.str("");
settings0.inconclusive = inconclusive;
// Raw tokens..
std::vector<std::string> files(1, filename);
std::istringstream istr(code);
const simplecpp::TokenList tokens1(istr, files, files[0]);
// Preprocess..
simplecpp::TokenList tokens2(files);
std::map<std::string, simplecpp::TokenList*> filedata;
simplecpp::preprocess(tokens2, tokens1, files, filedata, simplecpp::DUI());
// Tokenizer..
Tokenizer tokenizer(&settings0, this);
tokenizer.createTokens(&tokens2);
tokenizer.simplifyTokens1("");
// Run checks..
CheckCondition checkCondition;
checkCondition.runChecks(&tokenizer, &settings0, this);
}
void assignAndCompare() {
// &
check("void foo(int x)\n"
"{\n"
" int y = x & 4;\n"
" if (y == 3);\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (style) Mismatching assignment and comparison, comparison 'y==3' is always false.\n", errout.str());
check("void foo(int x)\n"
"{\n"
" int y = x & 4;\n"
" if (y != 3);\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (style) Mismatching assignment and comparison, comparison 'y!=3' is always true.\n", errout.str());
// |
check("void foo(int x) {\n"
" int y = x | 0x14;\n"
" if (y == 0x710);\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==1808' is always false.\n", errout.str());
check("void foo(int x) {\n"
" int y = x | 0x14;\n"
" if (y == 0x71f);\n"
"}");
ASSERT_EQUALS("", errout.str());
// various simple assignments
check("void foo(int x) {\n"
" int y = (x+1) | 1;\n"
" if (y == 2);\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==2' is always false.\n", errout.str());
check("void foo() {\n"
" int y = 1 | x();\n"
" if (y == 2);\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==2' is always false.\n", errout.str());
// multiple conditions
check("void foo(int x) {\n"
" int y = x & 4;\n"
" if ((y == 3) && (z == 1));\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==3' is always false.\n", errout.str());
check("void foo(int x) {\n"
" int y = x & 4;\n"
" if ((x==123) || ((y == 3) && (z == 1)));\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==3' is always false.\n", errout.str());
check("void f(int x) {\n"
" int y = x & 7;\n"
" if (setvalue(&y) && y != 8);\n"
"}");
ASSERT_EQUALS("", errout.str());
// recursive checking into scopes
check("void f(int x) {\n"
" int y = x & 7;\n"
" if (z) y=0;\n"
" else { if (y==8); }\n" // always false
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (style) Mismatching assignment and comparison, comparison 'y==8' is always false.\n", errout.str());
// while
check("void f(int x) {\n"
" int y = x & 7;\n"
" while (y==8);\n" // local variable => always false
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching assignment and comparison, comparison 'y==8' is always false.\n", errout.str());
check("void f(int x) {\n"
" extern int y; y = x & 7;\n"
" while (y==8);\n" // non-local variable => no error
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" int a = 100;\n"
" while (x) {\n"
" int y = 16 | a;\n"
" while (y != 0) y--;\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void g(int x);\n"
"void f(int x) {\n"
" int a = 100;\n"
" while (x) {\n"
" int y = 16 | a;\n"
" while (y != 0) g(y);\n"
" }\n"
"}");
ASSERT_EQUALS(
"[test.cpp:5] -> [test.cpp:6]: (style) Mismatching assignment and comparison, comparison 'y!=0' is always true.\n",
errout.str());
check("void g(int &x);\n"
"void f(int x) {\n"
" int a = 100;\n"
" while (x) {\n"
" int y = 16 | a;\n"
" while (y != 0) g(y);\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// calling function
check("void f(int x) {\n"
" int y = x & 7;\n"
" do_something();\n"
" if (y==8);\n" // local variable => always false
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (style) Mismatching assignment and comparison, comparison 'y==8' is always false.\n", errout.str());
check("void f(int x) {\n"
" int y = x & 7;\n"
" do_something(&y);\n" // passing variable => no error
" if (y==8);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void do_something(int);\n"
"void f(int x) {\n"
" int y = x & 7;\n"
" do_something(y);\n"
" if (y==8);\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:5]: (style) Mismatching assignment and comparison, comparison 'y==8' is always false.\n", errout.str());
check("void f(int x) {\n"
" extern int y; y = x & 7;\n"
" do_something();\n"
" if (y==8);\n" // non-local variable => no error
"}");
ASSERT_EQUALS("", errout.str());
// #4434 : false positive: ?:
check("void f(int x) {\n"
" x = x & 1;\n"
" x = x & 1 ? 1 : -1;\n"
" if(x != -1) { }\n"
"}");
ASSERT_EQUALS("", errout.str());
// #4735
check("void f() {\n"
" int x = *(char*)&0x12345678;\n"
" if (x==18) { }\n"
"}");
ASSERT_EQUALS("", errout.str());
// bailout: no variable info
check("void foo(int x) {\n"
" y = 2 | x;\n" // y not declared => no error
" if(y == 1) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
// bailout: negative number
check("void foo(int x) {\n"
" int y = -2 | x;\n" // negative number => no error
" if (y==1) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
// bailout: pass variable to function
check("void foo(int x) {\n"
" int y = 2 | x;\n"
" bar(&y);\n" // pass variable to function => no error
" if (y==1) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
// no crash on unary operator& (#5643)
check("SdrObject* ApplyGraphicToObject() {\n"
" if (&rHitObject) {}\n"
" else if (rHitObject.IsClosedObj() && !&rHitObject) { }\n"
"}");
ASSERT_EQUALS("", errout.str());
// #5695: increment
check("void f(int a0, int n) {\n"
" int c = a0 & 3;\n"
" for (int a = 0; a < n; a++) {\n"
" c++;\n"
" if (c == 4)\n"
" c = 0;\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(int a) {\n" // #6662
" int x = a & 1;\n"
" while (x <= 4) {\n"
" if (x != 5) {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (style) Mismatching assignment and comparison, comparison 'x!=5' is always true.\n", errout.str());
check("void f(int a) {\n" // #6662
" int x = a & 1;\n"
" while ((x += 4) < 10) {\n"
" if (x != 5) {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int x = 100;\n"
" while (x) {\n"
" g(x);\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void g(int x);\n"
"void f() {\n"
" int x = 100;\n"
" while (x) {\n"
" g(x);\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (style) Condition 'x' is always true\n", errout.str());
check("void g(int & x);\n"
"void f() {\n"
" int x = 100;\n"
" while (x) {\n"
" g(x);\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void mismatchingBitAnd() {
check("void f(int a) {\n"
" int b = a & 0xf0;\n"
" b &= 1;\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching bitmasks. Result is always 0 (X = Y & 0xf0; Z = X & 0x1; => Z=0).\n", errout.str());
check("void f(int a) {\n"
" int b = a & 0xf0;\n"
" int c = b & 1;\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching bitmasks. Result is always 0 (X = Y & 0xf0; Z = X & 0x1; => Z=0).\n", errout.str());
check("void f(int a) {\n"
" int b = a;"
" switch (x) {\n"
" case 1: b &= 1; break;\n"
" case 2: b &= 2; break;\n"
" };\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void comparison() {
// CheckCondition::comparison test cases
// '=='
check("void f(int a) {\n assert( (a & 0x07) == 8U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X & 0x7) == 0x8' is always false.\n",errout.str());
check("void f(int a) {\n assert( (a & b & 4 & c ) == 3 );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X & 0x4) == 0x3' is always false.\n", errout.str());
check("void f(int a) {\n assert( (a | 0x07) == 8U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X | 0x7) == 0x8' is always false.\n",errout.str());
check("void f(int a) {\n assert( (a & 0x07) == 7U );\n}");
ASSERT_EQUALS("", errout.str());
check("void f(int a) {\n assert( (a | 0x01) == -15 );\n}");
ASSERT_EQUALS("", errout.str());
// '!='
check("void f(int a) {\n assert( (a & 0x07) != 8U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X & 0x7) != 0x8' is always true.\n",errout.str());
check("void f(int a) {\n assert( (a | 0x07) != 8U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X | 0x7) != 0x8' is always true.\n",errout.str());
check("void f(int a) {\n assert( (a & 0x07) != 7U );\n}");
ASSERT_EQUALS("", errout.str());
check("void f(int a) {\n assert( (a | 0x07) != 7U );\n}");
ASSERT_EQUALS("", errout.str());
// '>='
check("void f(int a) {\n assert( (a & 0x07) >= 8U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X & 0x7) >= 0x8' is always false.\n",errout.str());
check("void f(unsigned int a) {\n assert( (a | 0x7) >= 7U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X | 0x7) >= 0x7' is always true.\n",errout.str());
check("void f(int a) {\n assert( (a & 0x07) >= 7U );\n}");
ASSERT_EQUALS("",errout.str());
check("void f(int a) {\n assert( (a | 0x07) >= 8U );\n}");
ASSERT_EQUALS("",errout.str()); //correct for negative 'a'
// '>'
check("void f(int a) {\n assert( (a & 0x07) > 7U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X & 0x7) > 0x7' is always false.\n",errout.str());
check("void f(unsigned int a) {\n assert( (a | 0x7) > 6U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X | 0x7) > 0x6' is always true.\n",errout.str());
check("void f(int a) {\n assert( (a & 0x07) > 6U );\n}");
ASSERT_EQUALS("",errout.str());
check("void f(int a) {\n assert( (a | 0x07) > 7U );\n}");
ASSERT_EQUALS("",errout.str()); //correct for negative 'a'
// '<='
check("void f(int a) {\n assert( (a & 0x07) <= 7U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X & 0x7) <= 0x7' is always true.\n",errout.str());
check("void f(unsigned int a) {\n assert( (a | 0x08) <= 7U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X | 0x8) <= 0x7' is always false.\n",errout.str());
check("void f(int a) {\n assert( (a & 0x07) <= 6U );\n}");
ASSERT_EQUALS("",errout.str());
check("void f(int a) {\n assert( (a | 0x08) <= 7U );\n}");
ASSERT_EQUALS("",errout.str()); //correct for negative 'a'
// '<'
check("void f(int a) {\n assert( (a & 0x07) < 8U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X & 0x7) < 0x8' is always true.\n",errout.str());
check("void f(unsigned int a) {\n assert( (a | 0x07) < 7U );\n}");
ASSERT_EQUALS("[test.cpp:2]: (style) Expression '(X | 0x7) < 0x7' is always false.\n",errout.str());
check("void f(int a) {\n assert( (a & 0x07) < 3U );\n}");
ASSERT_EQUALS("",errout.str());
check("void f(int a) {\n assert( (a | 0x07) < 7U );\n}");
ASSERT_EQUALS("",errout.str()); //correct for negative 'a'
}
void multicompare() {
check("void foo(int x)\n"
"{\n"
" if (x & 7);\n"
" else { if (x == 1); }\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (style) Expression is always false because 'else if' condition matches previous condition at line 3.\n", errout.str());
check("void foo(int x)\n"
"{\n"
" if (x & 7);\n"
" else { if (x & 1); }\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (style) Expression is always false because 'else if' condition matches previous condition at line 3.\n", errout.str());
check("extern int bar() __attribute__((pure));\n"
"void foo(int x)\n"
"{\n"
" if ( bar() >1 && b) {}\n"
" else if (bar() >1 && b) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:5]: (style) Expression is always false because 'else if' condition matches previous condition at line 4.\n", errout.str());
checkPureFunction("extern int bar();\n"
"void foo(int x)\n"
"{\n"
" if ( bar() >1 && b) {}\n"
" else if (bar() >1 && b) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:5]: (style) Expression is always false because 'else if' condition matches previous condition at line 4.\n", errout.str());
// 7284
check("void foo() {\n"
" if (a) {}\n"
" else if (!!a) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());
}
void checkPureFunction(const char code[]) {
// Clear the error buffer..
errout.str("");
// Tokenize..
Tokenizer tokenizer(&settings1, this);
std::istringstream istr(code);
tokenizer.tokenize(istr, "test.cpp");
CheckCondition checkCondition;
checkCondition.runChecks(&tokenizer, &settings1, this);
}
void overlappingElseIfCondition() {
check("void f(int a, int &b) {\n"
" if (a) { b = 1; }\n"
" else { if (a) { b = 2; } }\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Condition 'a' is always false\n", errout.str());
check("void f(int a, int &b) {\n"
" if (a) { b = 1; }\n"
" else { if (a) { b = 2; } }\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Condition 'a' is always false\n", errout.str());
check("void f(int a, int &b) {\n"
" if (a == 1) { b = 1; }\n"
" else { if (a == 2) { b = 2; }\n"
" else { if (a == 1) { b = 3; } } }\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (style) Condition 'a==1' is always false\n", errout.str());
check("void f(int a, int &b) {\n"
" if (a == 1) { b = 1; }\n"
" else { if (a == 2) { b = 2; }\n"
" else { if (a == 2) { b = 3; } } }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (style) Condition 'a==2' is always false\n", errout.str());
check("void f(int a, int &b) {\n"
" if (a++) { b = 1; }\n"
" else { if (a++) { b = 2; }\n"
" else { if (a++) { b = 3; } } }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int a, int &b) {\n"
" if (!strtok(NULL, \" \")) { b = 1; }\n"
" else { if (!strtok(NULL, \" \")) { b = 2; } }\n"
"}");
ASSERT_EQUALS("", errout.str());
{
check("void f(Class &c) {\n"
" if (c.dostuff() == 3) {}\n"
" else { if (c.dostuff() == 3) {} }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(const Class &c) {\n"
" if (c.dostuff() == 3) {}\n"
" else { if (c.dostuff() == 3) {} }\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());
}
check("void f(int a, int &b) {\n"
" x = x / 2;\n"
" if (x < 100) { b = 1; }\n"
" else { x = x / 2; if (x < 100) { b = 2; } }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int i) {\n"
" if(i == 0x02e2000000 || i == 0xa0c6000000)\n"
" foo(i);\n"
"}");
ASSERT_EQUALS("", errout.str());
// ticket 3689 ( avoid false positive )
check("int fitInt(long long int nValue){\n"
" if( nValue < 0x7fffffffLL )\n"
" {\n"
" return 32;\n"
" }\n"
" if( nValue < 0x7fffffffffffLL )\n"
" {\n"
" return 48;\n"
" }\n"
" else {\n"
" if( nValue < 0x7fffffffffffffffLL )\n"
" {\n"
" return 64;\n"
" } else\n"
" {\n"
" return -1;\n"
" }\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(WIDGET *widget) {\n"
" if (dynamic_cast<BUTTON*>(widget)){}\n"
" else if (dynamic_cast<LABEL*>(widget)){}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n" // #6482
" if (x & 1) {}\n"
" else if (x == 0) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x & 15) {}\n"
" else if (x == 40) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());
check("void f(int x) {\n"
" if (x == sizeof(double)) {}\n"
" else { if (x == sizeof(long double)) {} }"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x & 0x08) {}\n"
" else if (x & 0xF8) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x & 0xF8) {}\n"
" else if (x & 0x08) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());
check("void f(bool a, bool b) {\n"
" if(a && b){}\n"
" else if( !!b && !!a){}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());
check("void f(bool a, bool b) {\n"
" if(a && b){}\n"
" else if( !!b && a){}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());
check("void f(bool a, bool b) {\n"
" if(a && b){}\n"
" else if( b && !!a){}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());
check("void f(bool a, bool b) {\n"
" if(a && b){}\n"
" else if( b && !(!a)){}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());
check("void f(bool a, bool b) {\n"
" if(a && b){}\n"
" else if( !!b && !(!a)){}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Expression is always false because 'else if' condition matches previous condition at line 2.\n", errout.str());
check("void f(bool a, bool b) {\n"
" if(a && b){}\n"
" else if( !!(b) && !!(a+b)){}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #8168
check("enum MaskValues\n"
"{\n"
" Value1 = 0x00000001,\n"
" Value2 = 0x00000002\n"
"};\n"
"void TestFunction(int value) {\n"
" if ( value & (int)Value1 ) {}\n"
" else if ( value & (int)Value2 ) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void oppositeElseIfCondition() {
setMultiline();
check("void f(int x) {\n"
" if (x) {}\n"
" else if (!x) {}\n"
"}");
ASSERT_EQUALS("test.cpp:3:style:Condition '!x' is always true\n"
"test.cpp:2:note:condition 'x'\n"
"test.cpp:3:note:Condition '!x' is always true\n", errout.str());
check("void f(int x) {\n"
" int y = x;\n"
" if (x) {}\n"
" else if (!y) {}\n"
"}");
ASSERT_EQUALS("test.cpp:4:style:Expression is always true because 'else if' condition is opposite to previous condition at line 3.\n"
"test.cpp:2:note:'y' is assigned value 'x' here.\n"
"test.cpp:3:note:first condition\n"
"test.cpp:4:note:else if condition is opposite to first condition\n", errout.str());
}
void checkBadBitmaskCheck() {
check("bool f(int x) {\n"
" bool b = x | 0x02;\n"
" return b;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());
check("bool f(int x) {\n"
" bool b = 0x02 | x;\n"
" return b;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());
check("int f(int x) {\n"
" int b = x | 0x02;\n"
" return b;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("bool f(int x) {\n"
" bool b = x & 0x02;\n"
" return b;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("bool f(int x) {\n"
" if(x | 0x02)\n"
" return b;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());
check("bool f(int x) {\n"
" int y = 0x1;\n"
" if(b) y = 0;\n"
" if(x | y)\n"
" return b;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("bool f(int x) {\n"
" foo(a && (x | 0x02));\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());
check("int f(int x) {\n"
" return (x | 0x02) ? 0 : 5;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());
check("int f(int x) {\n"
" return x ? (x | 0x02) : 5;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("bool f(int x) {\n"
" return x | 0x02;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());
check("bool f(int x) {\n"
" if (x) {\n"
" return x | 0x02;\n"
" }\n"
" return 0;\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());
check("const bool f(int x) {\n"
" return x | 0x02;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());
check("struct F {\n"
" static const bool f(int x) {\n"
" return x | 0x02;\n"
" }\n"
"};");
ASSERT_EQUALS("[test.cpp:3]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());
check("struct F {\n"
" typedef bool b_t;\n"
"};\n"
"F::b_t f(int x) {\n"
" return x | 0x02;\n"
"}");
ASSERT_EQUALS("[test.cpp:5]: (warning) Result of operator '|' is always true if one operand is non-zero. Did you intend to use '&'?\n", errout.str());
check("int f(int x) {\n"
" return x | 0x02;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void create_rop_masks_4( rop_mask_bits *bits) {\n"
"DWORD mask_offset;\n"
"BYTE *and_bits = bits->and;\n"
"rop_mask *rop_mask;\n"
"and_bits[mask_offset] |= (rop_mask->and & 0x0f);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(unsigned a, unsigned b) {\n"
" unsigned cmd1 = b & 0x0F;\n"
" if (cmd1 | a) {\n"
" if (b == 0x0C) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void incorrectLogicOperator1() {
check("void f(int x) {\n"
" if ((x != 1) || (x != 3))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x != 1 || x != 3.\n", errout.str());
check("void f(int x) {\n"
" if (1 != x || 3 != x)\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x != 1 || x != 3.\n", errout.str());
check("void f(int x) {\n"
" if (x<0 && !x) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 0 && !x.\n", errout.str());
check("void f(int x) {\n"
" if (x==0 && x) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x == 0 && x.\n", errout.str());
check("void f(int x) {\n" // ast..
" if (y == 1 && x == 1 && x == 7) { }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x == 1 && x == 7.\n", errout.str());
check("void f(int x, int y) {\n"
" if (x != 1 || y != 1)\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
check("void f(int x, int y) {\n"
" if ((y == 1) && (x != 1) || (x != 3))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
check("void f(int x, int y) {\n"
" if ((x != 1) || (x != 3) && (y == 1))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if ((x != 1) && (x != 3))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if ((x == 1) || (x == 3))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
check("void f(int x, int y) {\n"
" if ((x != 1) || (y != 3))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
check("void f(int x, int y) {\n"
" if ((x != hotdog) || (y != hotdog))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
check("void f(int x, int y) {\n"
" if ((x != 5) || (y != 5))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if ((x != 5) || (x != 6))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x != 5 || x != 6.\n", errout.str());
check("void f(unsigned int a, unsigned int b, unsigned int c) {\n"
" if((a != b) || (c != b) || (c != a))\n"
" {\n"
" return true;\n"
" }\n"
" return false;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
}
void incorrectLogicOperator2() {
check("void f(float x) {\n"
" if ((x == 1) && (x == 1.0))\n"
" a++;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if ((x == 1) && (x == 0x00000001))\n"
" a++;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x == 1 && x == 3)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x == 1 && x == 3.\n", errout.str());
check("void f(int x) {\n"
" if (x == 1.0 && x == 3.0)\n"
" a++;\n"
"}");
ASSERT_EQUALS("", errout.str()); // float comparisons with == and != are not checked right now - such comparison is a bad idea
check("void f(float x) {\n"
" if (x == 1 && x == 1.0)\n"
" a++;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void bar(float f) {\n" // #5246
" if ((f > 0) && (f < 1)) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x < 1 && x > 1)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 1.\n", errout.str());
check("void f(int x) {\n"
" if (x < 1.0 && x > 1.0)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1.0 && x > 1.0.\n", errout.str());
check("void f(int x) {\n"
" if (x < 1 && x > 1.0)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 1.0.\n", errout.str());
check("void f(int x) {\n"
" if (x >= 1.0 && x <= 1.001)\n"
" a++;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x < 1 && x > 3)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 3.\n", errout.str());
check("void f(float x) {\n"
" if (x < 1.0 && x > 3.0)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1.0 && x > 3.0.\n", errout.str());
check("void f(int x) {\n"
" if (1 > x && 3 < x)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 3.\n", errout.str());
check("void f(int x) {\n"
" if (x < 3 && x > 1)\n"
" a++;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x > 3 || x < 10)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x > 3 || x < 10.\n", errout.str());
check("void f(int x) {\n"
" if (x >= 3 || x <= 10)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x >= 3 || x <= 10.\n", errout.str());
check("void f(int x) {\n"
" if (x >= 3 || x < 10)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x >= 3 || x < 10.\n", errout.str());
check("void f(int x) {\n"
" if (x > 3 || x <= 10)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x > 3 || x <= 10.\n", errout.str());
check("void f(int x) {\n"
" if (x > 3 || x < 3)\n"
" a++;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x >= 3 || x <= 3)\n"
" a++;\n"
"}"
);
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x >= 3 || x <= 3.\n", errout.str());
check("void f(int x) {\n"
" if (x >= 3 || x < 3)\n"
" a++;\n"
"}"
);
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x >= 3 || x < 3.\n", errout.str());
check("void f(int x) {\n"
" if (x > 3 || x <= 3)\n"
" a++;\n"
"}"
);
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x > 3 || x <= 3.\n", errout.str());
check("void f(int x) {\n"
" if((x==3) && (x!=4))\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 3', the comparison 'x != 4' is always true.\n", errout.str());
check("void f(int x) {\n"
" if ((x!=4) && (x==3))\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 3', the comparison 'x != 4' is always true.\n", errout.str());
check("void f(int x) {\n"
" if ((x==3) || (x!=4))\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 3', the comparison 'x != 4' is always true.\n", errout.str());
check("void f(int x) {\n"
" if ((x!=4) || (x==3))\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 3', the comparison 'x != 4' is always true.\n", errout.str());
check("void f(int x) {\n"
" if ((x==3) && (x!=3))\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x == 3 && x != 3.\n", errout.str());
check("void f(int x) {\n"
" if ((x==6) || (x!=6))\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: x == 6 || x != 6.\n", errout.str());
check("void f(int x) {\n"
" if (x > 10 || x < 3)\n"
" a++;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x > 5 && x == 1)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x > 5 && x == 1.\n", errout.str());
check("void f(int x) {\n"
" if (x > 5 && x == 6)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 6', the comparison 'x > 5' is always true.\n", errout.str());
// #3419
check("void f() {\n"
" if ( &q != &a && &q != &b ) { }\n"
"}");
ASSERT_EQUALS("", errout.str());
// #3676
check("void f(int m_x2, int w, int x) {\n"
" if (x + w - 1 > m_x2 || m_x2 < 0 )\n"
" m_x2 = x + w - 1;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(float x) {\n" // x+1 => x
" if (x <= 1.0e20 && x >= -1.0e20) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(float x) {\n" // x+1 => x
" if (x >= 1.0e20 && x <= 1.0e21) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(float x) {\n" // x+1 => x
" if (x <= -1.0e20 && x >= -1.0e21) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void incorrectLogicOperator3() {
check("void f(int x, bool& b) {\n"
" b = x > 5 && x == 1;\n"
" c = x < 1 && x == 3;\n"
" d = x >= 5 && x == 1;\n"
" e = x <= 1 && x == 3;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x > 5 && x == 1.\n"
"[test.cpp:3]: (warning) Logical conjunction always evaluates to false: x < 1 && x == 3.\n"
"[test.cpp:4]: (warning) Logical conjunction always evaluates to false: x >= 5 && x == 1.\n"
"[test.cpp:5]: (warning) Logical conjunction always evaluates to false: x <= 1 && x == 3.\n", errout.str());
}
void incorrectLogicOperator4() {
check("#define ZERO 0\n"
"void f(int x) {\n"
" if (x && x != ZERO) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void incorrectLogicOperator5() { // complex expressions
check("void f(int x) {\n"
" if (x+3 > 2 || x+3 < 10) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: EXPR > 2 || EXPR < 10.\n", errout.str());
}
void incorrectLogicOperator6() { // char literals
check("void f(char x) {\n"
" if (x == '1' || x == '2') {}\n"
"}", "test.cpp", true);
ASSERT_EQUALS("", errout.str());
check("void f(char x) {\n"
" if (x == '1' && x == '2') {}\n"
"}", "test.cpp", true);
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x == '1' && x == '2'.\n", errout.str());
check("int f(char c) {\n"
" return (c >= 'a' && c <= 'z');\n"
"}", "test.cpp", true);
ASSERT_EQUALS("", errout.str());
check("int f(char c) {\n"
" return (c <= 'a' && c >= 'z');\n"
"}", "test.cpp", true);
ASSERT_EQUALS("[test.cpp:2]: (warning, inconclusive) Logical conjunction always evaluates to false: c <= 'a' && c >= 'z'.\n", errout.str());
check("int f(char c) {\n"
" return (c <= 'a' && c >= 'z');\n"
"}", "test.cpp", false);
ASSERT_EQUALS("", errout.str());
}
void incorrectLogicOperator7() { // opposite expressions
check("void f(int i) {\n"
" if (i || !i) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: i || !(i).\n", errout.str());
check("void f(int a, int b) {\n"
" if (a>b || a<=b) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical disjunction always evaluates to true: a > b || a <= b.\n", errout.str());
check("void f(int a, int b) {\n"
" if (a>b || a<b) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
// #6064 False positive incorrectLogicOperator - invalid assumption about template type?
check("template<typename T> T icdf( const T uniform ) {\n"
" if ((0<uniform) && (uniform<1))\n"
" {}\n"
"}");
ASSERT_EQUALS("", errout.str());
// #6081 False positive: incorrectLogicOperator, with close negative comparisons
check("double neg = -1.0 - 1.0e-13;\n"
"void foo() {\n"
" if ((neg < -1.0) && (neg > -1.0 - 1.0e-12))\n"
" return;\n"
" else\n"
" return;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void incorrectLogicOperator8() { // opposite expressions
check("void f(int i) {\n"
" if (!(i!=10) && !(i!=20)) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: !(i != 10) && !(i != 20).\n", errout.str());
}
void incorrectLogicOperator9() { // #6069 "False positive incorrectLogicOperator due to dynamic_cast"
check("class MyType;\n"
"class OtherType;\n"
"void foo (OtherType* obj) { \n"
" assert((!obj) || dynamic_cast<MyType*>(obj));\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void incorrectLogicOperator10() { // #7794 - enum
check("typedef enum { A, B } Type_t;\n"
"void f(Type_t t) {\n"
" if ((t == A) && (t == B))\n"
" {}\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (warning) Logical conjunction always evaluates to false: t == 0 && t == 1.\n", errout.str());
}
void incorrectLogicOperator11() {
check("void foo(int i, const int n) { if ( i < n && i == n ) {} }");
ASSERT_EQUALS("[test.cpp:1]: (warning) Logical conjunction always evaluates to false: i < n && i == n.\n", errout.str());
check("void foo(int i, const int n) { if ( i > n && i == n ) {} }");
ASSERT_EQUALS("[test.cpp:1]: (warning) Logical conjunction always evaluates to false: i > n && i == n.\n", errout.str());
check("void foo(int i, const int n) { if ( i == n && i > n ) {} }");
ASSERT_EQUALS("[test.cpp:1]: (warning) Logical conjunction always evaluates to false: i == n && i > n.\n", errout.str());
check("void foo(int i, const int n) { if ( i == n && i < n ) {} }");
ASSERT_EQUALS("[test.cpp:1]: (warning) Logical conjunction always evaluates to false: i == n && i < n.\n", errout.str());
}
void incorrectLogicOperator12() { // #8696
check("struct A {\n"
" void f() const;\n"
"};\n"
"void foo(A a) {\n"
" A x = a;\n"
" A y = a;\n"
" y.f();\n"
" if (a > x && a < y)\n"
" return;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:6] -> [test.cpp:8]: (warning) Logical conjunction always evaluates to false: a > x && a < y.\n", errout.str());
check("struct A {\n"
" void f();\n"
"};\n"
"void foo(A a) {\n"
" A x = a;\n"
" A y = a;\n"
" y.f();\n"
" if (a > x && a < y)\n"
" return;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void foo(A a) {\n"
" A x = a;\n"
" A y = a;\n"
" y.f();\n"
" if (a > x && a < y)\n"
" return;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void foo(A a) {\n"
" const A x = a;\n"
" const A y = a;\n"
" y.f();\n"
" if (a > x && a < y)\n"
" return;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3] -> [test.cpp:5]: (warning) Logical conjunction always evaluates to false: a > x && a < y.\n", errout.str());
}
void incorrectLogicOperator13() {
// 8780
check("void f(const int &v) {\n"
" const int x=v;\n"
" if ((v == 1) && (x == 2)) {;}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Logical conjunction always evaluates to false: v == 1 && x == 2.\n", errout.str());
check("void f2(const int *v) {\n"
" const int *x=v;\n"
" if ((*v == 1) && (*x == 2)) {;}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Logical conjunction always evaluates to false: *(v) == 1 && *(x) == 2.\n", errout.str());
}
void incorrectLogicOperator14() {
check("static const std ::string h;\n"
"class i {\n"
"public:\n"
" struct j {\n"
" std ::string k;\n"
" std ::string l;\n"
" };\n"
" struct a {\n"
" enum { m = 1 };\n"
" };\n"
"} b;\n"
"namespace n {\n"
"class c;\n"
"}\n"
"struct o {\n"
" enum { p, d, q, r };\n"
" enum { e, f };\n"
"\n"
"public:\n"
" class j {\n"
" public:\n"
" class s {\n"
" std ::string a;\n"
" };\n"
" };\n"
"};\n"
"namespace n {\n"
"class b;\n"
"}\n"
"namespace aa {\n"
"class d {\n"
"public:\n"
" char t;\n"
" enum {} u;\n"
"};\n"
"} // namespace aa\n"
"namespace aa {\n"
"struct e {};\n"
"} // namespace aa\n"
"class a;\n"
"class w {\n"
"public:\n"
" enum { x };\n"
" struct {\n"
" } y;\n"
" std ::string z;\n"
"};\n"
"class ab {\n"
" friend class c;\n"
"\n"
"public:\n"
" class ac {\n"
" void e(const ac &v) const;\n"
" };\n"
"};\n"
"class f;\n"
"class ad {\n"
" friend class e;\n"
" enum { e, ae, ag, ah, ai, aj, ak, a, b };\n"
" class c {};\n"
" class d {\n"
" enum am { f, an, ao, ap, aq, ar, b, as, at, c, au };\n"
" enum av { aw, ax, ay, az, e, ba, bb, bc, bd, a };\n"
" struct b {\n"
" am action;\n"
" av c;\n"
" };\n"
" };\n"
" class e {\n"
" public:\n"
" std ::string e;\n"
" class f {\n"
" } f;\n"
" class be {\n"
" public:\n"
" };\n"
" std ::vector<be> bf;\n"
" enum { bg, b } c;\n"
" };\n"
" struct bh {\n"
" std ::map<int, d> b;\n"
" };\n"
" std ::map<std ::string, bh> bi;\n"
" struct {\n"
" int b;\n"
" char bj;\n"
" } bk;\n"
" class a {\n"
" public:\n"
" std ::set<std ::string> b;\n"
" };\n"
"};\n"
"class bl;\n"
"class al;\n"
"class bm;\n"
"class f;\n"
"class b;\n"
"class bn;\n"
"namespace bo {\n"
"class bp {\n"
"public:\n"
" typedef std ::pair<const f *, std ::string> bq;\n"
" typedef std ::list<bq> br;\n"
"};\n"
"const bo ::bp *dg(const f *a, const al *b);\n"
"} // namespace bo\n"
"const bn *dh(const f *d, bo ::bp ::br &bs);\n"
"class f {\n"
"public:\n"
" struct bt {};\n"
" std ::vector<a> f;\n"
"};\n"
"class bu;\n"
"class a;\n"
"class c;\n"
"struct bv {};\n"
"class af {\n"
"private:\n"
"public:\n"
" enum { b, d, e, f, c, bw };\n"
" void a(int c);\n"
" af *bx() const;\n"
"};\n"
"namespace by {\n"
"class b;\n"
"}\n"
"class b {\n"
"public:\n"
" bool d, c;\n"
"};\n"
"class bz;\n"
"class f;\n"
"class ca {\n"
" friend class b;\n"
"\n"
"public:\n"
" const bm *cb() const { return cc; }\n"
" f *d(f *e, bool f) const;\n"
" int e() { return ++cd; }\n"
" bl *const c;\n"
" bm *cc;\n"
" std ::map<std ::string, int> ce;\n"
" int cd;\n"
" bz *a;\n"
"};\n"
"namespace n {\n"
"class c;\n"
"class d;\n"
"} // namespace n\n"
"class cf {\n"
"public:\n"
" explicit cf(const std ::string &aname);\n"
" cf(const std ::string &aname, const ca *cg, const al *ch, bl *ci)\n"
" : cj(cg), ck(ch), cl(ci), cn(aname) {}\n"
"\n"
"protected:\n"
" const ca *const cj;\n"
" const al *const ck;\n"
" bl *const cl;\n"
" const std ::string cn;\n"
"};\n"
"class cm : public cf {\n"
"public:\n"
" void cp();\n"
" std ::string d() const;\n"
"};\n"
"struct co {\n"
" co();\n"
" const bu *a;\n"
" enum f {};\n"
" enum {\n"
" b = (1 << 0),\n"
" c = (1 << 1),\n"
" };\n"
" void d(bool e);\n"
"};\n"
"class bu {\n"
" friend class e;\n"
"\n"
"public:\n"
" struct f {};\n"
" enum { d, cr, cq, ct, cs, e, a, b, c, dd, cu, cv, cw, cx, cy, cz, da };\n"
" const f *db;\n"
" const af *dc;\n"
"} f{};\n"
"class bm {\n"
"public:\n"
" std ::list<bu> df;\n"
" std ::vector<const bu *> de;\n"
" mutable std ::set<std ::string> f;\n"
"};\n"
"void cm ::cp() {\n"
" const bm *a = cj->cb();\n"
" for (const bu *b : a->de)\n"
" for (af *c = b->dc->bx();;) {\n"
" af *d = c;\n"
" af *e = c;\n"
" bool f(d);\n"
" bool g(e);\n"
" if (f && g)\n"
" ;\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void secondAlwaysTrueFalseWhenFirstTrueError() {
check("void f(int x) {\n"
" if (x > 5 && x != 1)\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x > 5', the comparison 'x != 1' is always true.\n", errout.str());
check("void f(int x) {\n"
" if (x > 5 && x != 6)\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if ((x > 5) && (x != 1))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x > 5', the comparison 'x != 1' is always true.\n", errout.str());
check("void f(int x) {\n"
" if ((x > 5) && (x != 6))\n"
" a++;\n"
"}\n"
);
ASSERT_EQUALS("", errout.str());
check("void f(int x, bool& b) {\n"
" b = x > 3 || x == 4;\n"
" c = x < 5 || x == 4;\n"
" d = x >= 3 || x == 4;\n"
" e = x <= 5 || x == 4;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x == 4', the comparison 'x > 3' is always true.\n"
"[test.cpp:3]: (style) Redundant condition: If 'x == 4', the comparison 'x < 5' is always true.\n"
"[test.cpp:4]: (style) Redundant condition: If 'x == 4', the comparison 'x >= 3' is always true.\n"
"[test.cpp:5]: (style) Redundant condition: If 'x == 4', the comparison 'x <= 5' is always true.\n", errout.str());
check("void f(int x, bool& b) {\n"
" b = x > 5 || x != 1;\n"
" c = x < 1 || x != 3;\n"
" d = x >= 5 || x != 1;\n"
" e = x <= 1 || x != 3;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x > 5', the comparison 'x != 1' is always true.\n"
"[test.cpp:3]: (style) Redundant condition: If 'x < 1', the comparison 'x != 3' is always true.\n"
"[test.cpp:4]: (style) Redundant condition: If 'x >= 5', the comparison 'x != 1' is always true.\n"
"[test.cpp:5]: (style) Redundant condition: If 'x <= 1', the comparison 'x != 3' is always true.\n", errout.str());
check("void f(int x, bool& b) {\n"
" b = x > 6 && x > 5;\n"
" c = x > 5 || x > 6;\n"
" d = x < 6 && x < 5;\n"
" e = x < 5 || x < 6;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: If 'x > 6', the comparison 'x > 5' is always true.\n"
"[test.cpp:3]: (style) Redundant condition: If 'x > 6', the comparison 'x > 5' is always true.\n"
"[test.cpp:4]: (style) Redundant condition: If 'x < 5', the comparison 'x < 6' is always true.\n"
"[test.cpp:5]: (style) Redundant condition: If 'x < 5', the comparison 'x < 6' is always true.\n", errout.str());
}
void incorrectLogicOp_condSwapping() {
check("void f(int x) {\n"
" if (x < 1 && x > 3)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 3.\n", errout.str());
check("void f(int x) {\n"
" if (1 > x && x > 3)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 3.\n", errout.str());
check("void f(int x) {\n"
" if (x < 1 && 3 < x)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 3.\n", errout.str());
check("void f(int x) {\n"
" if (1 > x && 3 < x)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x < 1 && x > 3.\n", errout.str());
check("void f(int x) {\n"
" if (x > 3 && x < 1)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x > 3 && x < 1.\n", errout.str());
check("void f(int x) {\n"
" if (3 < x && x < 1)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x > 3 && x < 1.\n", errout.str());
check("void f(int x) {\n"
" if (x > 3 && 1 > x)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x > 3 && x < 1.\n", errout.str());
check("void f(int x) {\n"
" if (3 < x && 1 > x)\n"
" a++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Logical conjunction always evaluates to false: x > 3 && x < 1.\n", errout.str());
}
void modulo() {
check("bool f(bool& b1, bool& b2, bool& b3) {\n"
" b1 = a % 5 == 4;\n"
" b2 = a % c == 100000;\n"
" b3 = a % 5 == c;\n"
" return a % 5 == 5-p;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("bool f(bool& b1, bool& b2, bool& b3, bool& b4, bool& b5) {\n"
" b1 = a % 5 < 5;\n"
" b2 = a % 5 <= 5;\n"
" b3 = a % 5 == 5;\n"
" b4 = a % 5 != 5;\n"
" b5 = a % 5 >= 5;\n"
" return a % 5 > 5;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Comparison of modulo result is predetermined, because it is always less than 5.\n"
"[test.cpp:3]: (warning) Comparison of modulo result is predetermined, because it is always less than 5.\n"
"[test.cpp:4]: (warning) Comparison of modulo result is predetermined, because it is always less than 5.\n"
"[test.cpp:5]: (warning) Comparison of modulo result is predetermined, because it is always less than 5.\n"
"[test.cpp:6]: (warning) Comparison of modulo result is predetermined, because it is always less than 5.\n"
"[test.cpp:7]: (warning) Comparison of modulo result is predetermined, because it is always less than 5.\n", errout.str());
check("void f(bool& b1, bool& b2) {\n"
" b1 = bar() % 5 < 889;\n"
" if(x[593] % 5 <= 5)\n"
" b2 = x.a % 5 == 5;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Comparison of modulo result is predetermined, because it is always less than 5.\n"
"[test.cpp:3]: (warning) Comparison of modulo result is predetermined, because it is always less than 5.\n"
"[test.cpp:4]: (warning) Comparison of modulo result is predetermined, because it is always less than 5.\n", errout.str());
check("void f() {\n"
" if (a % 2 + b % 2 == 2)\n"
" foo();\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void oppositeInnerCondition() {
check("void foo(int a, int b) {\n"
" if(a==b)\n"
" if(a!=b)\n"
" cout << a;\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("bool foo(int a, int b) {\n"
" if(a==b)\n"
" return a!=b;\n"
" return false;\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Opposite inner 'return' condition leads to a dead code block.\n", errout.str());
check("void foo(int a, int b) {\n"
" if(a==b)\n"
" if(b!=a)\n"
" cout << a;\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void foo(int a) {\n"
" if(a >= 50) {\n"
" if(a < 50)\n"
" cout << a;\n"
" else\n"
" cout << 100;\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
// #4186
check("void foo(int a) {\n"
" if(a >= 50) {\n"
" if(a > 50)\n"
" cout << a;\n"
" else\n"
" cout << 100;\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// 4170
check("class foo {\n"
" void bar() {\n"
" if (tok == '(') {\n"
" next();\n"
" if (tok == ',') {\n"
" next();\n"
" if (tok != ',') {\n"
" op->reg2 = asm_parse_reg();\n"
" }\n"
" skip(',');\n"
" }\n"
" }\n"
" }\n"
" void next();\n"
" const char *tok;\n"
"};");
ASSERT_EQUALS("", errout.str());
check("void foo(int i)\n"
"{\n"
" if(i > 5) {\n"
" i = bar();\n"
" if(i < 5) {\n"
" cout << a;\n"
" }\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void foo(int& i) {\n"
" i=6;\n"
"}\n"
"void bar(int i) {\n"
" if(i>5) {\n"
" foo(i);\n"
" if(i<5) {\n"
" }\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void foo(int& i);\n"
"void bar() {\n"
" int i; i = func();\n"
" if(i>5) {\n"
" foo(i);\n"
" if(i<5) {\n"
" }\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void foo(int i);\n"
"void bar(int i) {\n"
" if(i>5) {\n"
" foo(i);\n"
" if(i<5) {\n"
" }\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:5]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void foo(const int &i);\n"
"void bar(int i) {\n"
" if(i>5) {\n"
" foo(i);\n"
" if(i<5) {\n"
" }\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:5]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void foo(int i);\n"
"void bar() {\n"
" int i; i = func();\n"
" if(i>5) {\n"
" foo(i);\n"
" if(i<5) {\n"
" }\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:6]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("class C { void f(int &i) const; };\n" // #7028 - variable is changed by const method
"void foo(C c, int i) {\n"
" if (i==5) {\n"
" c.f(i);\n"
" if (i != 5) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// see linux revision 1f80c0cc
check("int generic_write_sync(int,int,int);\n"
"\n"
"void cifs_writev(int i) {\n"
" int rc = __generic_file_aio_write();\n"
" if (rc > 0){\n"
" err = generic_write_sync(file, iocb->ki_pos - rc, rc);\n"
" if(rc < 0) {\n" // <- condition is always false
" err = rc;\n"
" }\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:7]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
// #5874 - array
check("void testOppositeConditions2() {\n"
" int array[2] = { 0, 0 };\n"
" if (array[0] < 2) {\n"
" array[0] += 5;\n"
" if (array[0] > 2) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// #6227 - FP caused by simplifications of casts and known variables
check("void foo(A *a) {\n"
" if(a) {\n"
" B *b = dynamic_cast<B*>(a);\n"
" if(!b) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void foo(int a) {\n"
" if(a) {\n"
" int b = a;\n"
" if(!b) {}\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void foo(unsigned u) {\n"
" if (u != 0) {\n"
" for (int i=0; i<32; i++) {\n"
" if (u == 0) {}\n" // <- don't warn
" u = x;\n"
" }\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// #8186
check("void f() {\n"
" for (int i=0;i<4;i++) {\n"
" if (i==5) {}\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
}
void oppositeInnerConditionPointers() {
check("void f(struct ABC *abc) {\n"
" struct AB *ab = abc->ab;\n"
" if (ab->a == 123){\n"
" do_something(abc);\n" // might change ab->a
" if (ab->a != 123) {\n"
" err = rc;\n"
" }\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void Fred::f() {\n" // daca: ace
" if (this->next_ == map_man_->table_) {\n"
" this->next_ = n;\n"
" if (this->next_ != map_man_->table_) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void test(float *f) {\n" // #7405
" if(*f>10) {\n"
" (*f) += 0.1f;\n"
" if(*f<10) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("int * f(int * x, int * y) {\n"
" if(!x) return x;\n"
" return y;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void oppositeInnerConditionClass() {
// #6095 - calling member function that might change the state
check("void f() {\n"
" const Fred fred;\n" // <- fred is const, warn
" if (fred.isValid()) {\n"
" fred.dostuff();\n"
" if (!fred.isValid()) {}\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:5]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("class Fred { public: bool isValid() const; void dostuff() const; };\n"
"void f() {\n"
" Fred fred;\n"
" if (fred.isValid()) {\n"
" fred.dostuff();\n" // <- dostuff() is const, warn
" if (!fred.isValid()) {}\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:6]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f() {\n"
" Fred fred;\n"
" if (fred.isValid()) {\n"
" fred.dostuff();\n"
" if (!fred.isValid()) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// #6385 "crash in Variable::getFlag()"
check("class TranslationHandler {\n"
"QTranslator *mTranslator;\n"
"void SetLanguage() {\n"
" if (mTranslator) {\n"
" qApp->removeTranslator(mTranslator);\n"
" }\n"
" }\n"
"};");
ASSERT_EQUALS("", errout.str()); // just don't crash...
check("bool f(std::ofstream &CFileStream) {\n" // #8198
" if(!CFileStream.good()) { return; }\n"
" CFileStream << \"abc\";\n"
" if (!CFileStream.good()) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void oppositeInnerConditionUndeclaredVariable() {
// #5731 - fp when undeclared variable is used
check("void f() {\n"
" if (x == -1){\n"
" x = do_something();\n"
" if (x != -1) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// #5750 - another fp when undeclared variable is used
check("void f() {\n"
" if (r < w){\n"
" r += 3;\n"
" if (r > w) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// #6574 - another fp when undeclared variable is used
check("void foo() {\n"
" if(i) {\n"
" i++;\n"
" if(!i) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// undeclared array
check("void f(int x) {\n"
" if (a[x] > 0) {\n"
" a[x] -= dt;\n"
" if (a[x] < 0) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// #6313 - false positive: opposite conditions in nested if blocks when condition changed
check("void Foo::Bar() {\n"
" if(var){\n"
" --var;\n"
" if(!var){}\n"
" else {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// daca hyphy
check("bool f() {\n"
" if (rec.lLength==0) {\n"
" rec.Delete(i);\n"
" if (rec.lLength!=0) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void oppositeInnerConditionAlias() {
check("void f() {\n"
" struct S s;\n"
" bool hasFailed = false;\n"
" s.status = &hasFailed;\n"
"\n"
" if (! hasFailed) {\n"
" doStuff(&s);\n"
" if (hasFailed) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void oppositeInnerCondition2() {
// first comparison: <
check("void f(int x) {\n"
"\n"
" if (x<4) {\n"
" if (x==5) {}\n" // <- Warning
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (warning) Opposite inner 'if' condition leads to a dead code block.\n",
errout.str());
check("void f(int x) {\n"
"\n"
" if (x<4) {\n"
" if (x!=5) {}\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (style) Condition 'x!=5' is always true\n", errout.str());
check("void f(int x) {\n"
"\n"
" if (x<4) {\n"
" if (x>5) {}\n" // <- Warning
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (warning) Opposite inner 'if' condition leads to a dead code block.\n",
errout.str());
check("void f(int x) {\n"
"\n"
" if (x<4) {\n"
" if (x>=5) {}\n" // <- Warning
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (warning) Opposite inner 'if' condition leads to a dead code block.\n",
errout.str());
check("void f(int x) {\n"
"\n"
" if (x<4) {\n"
" if (x<5) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x<4) {\n"
" if (x<=5) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x<5) {\n"
" if (x==4) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x<5) {\n"
" if (x!=4) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x<5) {\n"
" if (x>4) {}\n" // <- TODO
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x<5) {\n"
" if (x>=4) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x<5) {\n"
" if (x<4) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x<5) {\n"
" if (x<=4) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// first comparison: >
check("void f(int x) {\n"
"\n"
" if (x>4) {\n"
" if (x==5) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x>4) {\n"
" if (x>5) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x>4) {\n"
" if (x>=5) {}\n" // <- TODO
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x>4) {\n"
" if (x<5) {}\n" // <- TODO
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x>4) {\n"
" if (x<=5) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x>5) {\n"
" if (x==4) {}\n" // <- Warning
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (warning) Opposite inner 'if' condition leads to a dead code block.\n",
errout.str());
check("void f(int x) {\n"
"\n"
" if (x>5) {\n"
" if (x>4) {}\n" // <- TODO
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x>5) {\n"
" if (x>=4) {}\n" // <- TODO
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
"\n"
" if (x>5) {\n"
" if (x<4) {}\n" // <- Warning
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (warning) Opposite inner 'if' condition leads to a dead code block.\n",
errout.str());
check("void f(int x) {\n"
"\n"
" if (x>5) {\n"
" if (x<=4) {}\n" // <- Warning
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (warning) Opposite inner 'if' condition leads to a dead code block.\n",
errout.str());
check("void f(int x) {\n"
" if (x < 4) {\n"
" if (10 < x) {}\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
}
void oppositeInnerCondition3() {
check("void f3(char c) { if(c=='x') if(c=='y') {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f4(char *p) { if(*p=='x') if(*p=='y') {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f5(const char * const p) { if(*p=='x') if(*p=='y') {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f5(const char * const p) { if('x'==*p) if('y'==*p) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f6(char * const p) { if(*p=='x') if(*p=='y') {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f7(const char * p) { if(*p=='x') if(*p=='y') {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f8(int i) { if(i==4) if(i==2) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f9(int *p) { if (*p==4) if(*p==2) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f10(int * const p) { if (*p==4) if(*p==2) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f11(const int *p) { if (*p==4) if(*p==2) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f12(const int * const p) { if (*p==4) if(*p==2) {}}");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("struct foo {\n"
" int a;\n"
" int b;\n"
"};\n"
"void f(foo x) { if(x.a==4) if(x.b==2) {}} ");
ASSERT_EQUALS("", errout.str());
check("struct foo {\n"
" int a;\n"
" int b;\n"
"};\n"
"void f(foo x) { if(x.a==4) if(x.b==4) {}} ");
ASSERT_EQUALS("", errout.str());
check("void f3(char a, char b) { if(a==b) if(a==0) {}} ");
ASSERT_EQUALS("", errout.str());
check("void f(int x) { if (x == 1) if (x != 1) {} }");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
}
void oppositeInnerConditionAnd() {
check("void f(int x) {\n"
" if (a>3 && x > 100) {\n"
" if (x < 10) {}\n"
" }"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
}
void oppositeInnerConditionEmpty() {
check("void f1(const std::string &s) { if(s.size() > 42) if(s.empty()) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f1(const std::string &s) { if(s.size() > 0) if(s.empty()) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f1(const std::string &s) { if(s.size() < 0) if(s.empty()) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f1(const std::string &s) { if(s.empty()) if(s.size() > 42) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("template<class T> void f1(const T &s) { if(s.size() > 42) if(s.empty()) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f2(const std::wstring &s) { if(s.empty()) if(s.size() > 42) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f1(QString s) { if(s.isEmpty()) if(s.length() > 42) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Opposite inner 'if' condition leads to a dead code block.\n", errout.str());
check("void f1(const std::string &s, bool b) { if(s.empty() || ((s.size() == 1) && b)) {}} ");
ASSERT_EQUALS("", errout.str());
check("void f1(const std::string &x, const std::string &y) { if(x.size() > 42) if(y.empty()) {}} ");
ASSERT_EQUALS("", errout.str());
check("void f1(const std::string &x, const std::string &y) { if(y.empty()) if(x.size() > 42) {}} ");
ASSERT_EQUALS("", errout.str());
check("void f1(const std::string v[10]) { if(v[0].size() > 42) if(v[1].empty()) {}} ");
ASSERT_EQUALS("", errout.str());
check("void f1(const std::string &s) { if(s.size() <= 1) if(s.empty()) {}} ");
ASSERT_EQUALS("", errout.str());
check("void f1(const std::string &s) { if(s.size() <= 2) if(s.empty()) {}} ");
ASSERT_EQUALS("", errout.str());
check("void f1(const std::string &s) { if(s.size() < 2) if(s.empty()) {}} ");
ASSERT_EQUALS("", errout.str());
check("void f1(const std::string &s) { if(s.size() >= 0) if(s.empty()) {}} ");
ASSERT_EQUALS("", errout.str());
// TODO: These are identical condition since size cannot be negative
check("void f1(const std::string &s) { if(s.size() <= 0) if(s.empty()) {}} ");
ASSERT_EQUALS("", errout.str());
// TODO: These are identical condition since size cannot be negative
check("void f1(const std::string &s) { if(s.size() < 1) if(s.empty()) {}} ");
ASSERT_EQUALS("", errout.str());
}
void oppositeInnerConditionFollowVar() {
check("struct X {\n"
" void f() {\n"
" const int flag = get();\n"
" if (flag) {\n"
" bar();\n"
" if (!get()) {}\n"
" }\n"
" }\n"
" void bar();\n"
" int get() const;\n"
"};");
ASSERT_EQUALS("", errout.str());
check("class C {\n"
"public:\n"
" bool f() const { return x > 0; }\n"
" void g();\n"
" int x = 0;\n"
"};\n"
"\n"
"void C::g() {\n"
" bool b = f();\n"
" x += 1;\n"
" if (!b && f()) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void identicalInnerCondition() {
check("void f1(int a, int b) { if(a==b) if(a==b) {}}");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Identical inner 'if' condition is always true.\n", errout.str());
check("void f2(int a, int b) { if(a!=b) if(a!=b) {}}");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (warning) Identical inner 'if' condition is always true.\n", errout.str());
// #6645 false negative: condition is always false
check("void f(bool a, bool b) {\n"
" if(a && b) {\n"
" if(a) {}\n"
" else {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Identical inner 'if' condition is always true.\n", errout.str());
check("bool f(int a, int b) {\n"
" if(a == b) { return a == b; }\n"
" return false;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:2]: (warning) Identical inner 'return' condition is always true.\n", errout.str());
check("bool f(bool a) {\n"
" if(a) { return a; }\n"
" return false;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int* f(int* a, int * b) {\n"
" if(a) { return a; }\n"
" return b;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int* f(std::shared_ptr<int> a, std::shared_ptr<int> b) {\n"
" if(a.get()) { return a.get(); }\n"
" return b.get();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct A { int * x; };\n"
"int* f(A a, int * b) {\n"
" if(a.x) { return a.x; }\n"
" return b;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" uint32_t value;\n"
" get_value(&value);\n"
" int opt_function_capable = (value >> 28) & 1;\n"
" if (opt_function_capable) {\n"
" value = 0;\n"
" get_value (&value);\n"
" if ((value >> 28) & 1) {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void identicalConditionAfterEarlyExit() {
check("void f(int x) {\n"
" if (x > 100) { return; }\n"
" if (x > 100) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Identical condition 'x>100', second condition is always false\n", errout.str());
check("bool f(int x) {\n"
" if (x > 100) { return false; }\n"
" return x > 100;\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Identical condition 'x>100', second condition is always false\n", errout.str());
check("void f(int x) {\n"
" if (x > 100) { return; }\n"
" if (x > 100 || y > 100) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Identical condition 'x>100', second condition is always false\n", errout.str());
check("void f(int x) {\n"
" if (x > 100) { return; }\n"
" if (x > 100 && y > 100) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (warning) Identical condition 'x>100', second condition is always false\n", errout.str());
check("void f(int x) {\n"
" if (x > 100) { return; }\n"
" if (abc) {}\n"
" if (x > 100) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (warning) Identical condition 'x>100', second condition is always false\n", errout.str());
check("void f(int x) {\n"
" if (x > 100) { return; }\n"
" while (abc) { y = x; }\n"
" if (x > 100) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (warning) Identical condition 'x>100', second condition is always false\n", errout.str());
check("void f(int x) {\n" // #8217 - crash for incomplete code
" if (x > 100) { return; }\n"
" X(do);\n"
" if (x > 100) {}\n"
"}");
// TODO: we should probably throw unknownMacro InternalError. Complain that the macro X must be defined. We can't check the code well without the definition.
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (style) Condition 'x>100' is always false\n", errout.str());
check("void f(const int *i) {\n"
" if (!i) return;\n"
" if (!num1tok) { *num1 = *num2; }\n"
" if (!i) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (warning) Identical condition '!i', second condition is always false\n", errout.str());
check("void C::f(Tree &coreTree) {\n" // daca
" if(!coreTree.build())\n"
" return;\n"
" coreTree.dostuff();\n"
" if(!coreTree.build()) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct C { void f(const Tree &coreTree); };\n"
"void C::f(const Tree &coreTree) {\n"
" if(!coreTree.build())\n"
" return;\n"
" coreTree.dostuff();\n"
" if(!coreTree.build()) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:6]: (warning) Identical condition '!coreTree.build()', second condition is always false\n", errout.str());
check("void f(int x) {\n" // daca: labplot
" switch(type) {\n"
" case 1:\n"
" if (x == 0) return 1;\n"
" else return 2;\n"
" case 2:\n"
" if (x == 0) return 3;\n"
" else return 4;\n"
" }\n"
" return 0;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("static int failed = 0;\n"
"void f() {\n"
" if (failed) return;\n"
" checkBuffer();\n"
" if (failed) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
// daca icu
check("void f(const uint32_t *section, int32_t start) {\n"
" if(10<=section[start]) { return; }\n"
" if(++start<100 && 10<=section[start]) { }\n"
"}");
ASSERT_EQUALS("", errout.str());
// daca iqtree
check("void readNCBITree(std::istream &in) {\n"
" char ch;\n"
" in >> ch;\n"
" if (ch != '|') return;\n"
" in >> ch;\n"
" if (ch != '|') {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #8924
check("struct A {\n"
" void f() {\n"
" if (this->FileIndex >= 0) return;\n"
" this->FileIndex = 1 ;\n"
" if (this->FileIndex < 0) return;\n"
" }\n"
" int FileIndex; \n"
"};\n");
ASSERT_EQUALS("", errout.str());
}
void innerConditionModified() {
check("void f(int x, int y) {\n"
" if (x == 0) {\n"
" x += y;\n"
" if (x == 0) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x == 0) {\n"
" x += y;\n"
" if (x == 1) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(int * x, int * y) {\n"
" if (x[*y] == 0) {\n"
" (*y)++;\n"
" if (x[*y] == 0) {}\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
}
// clarify conditions with = and comparison
void clarifyCondition1() {
check("void f() {\n"
" if (x = b() < 0) {}\n" // don't simplify and verify this code
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Suspicious condition (assignment + comparison); Clarify expression with parentheses.\n", errout.str());
check("void f(int i) {\n"
" for (i = 0; i < 10; i++) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" x = a<int>(); if (x) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" if (x = b < 0 ? 1 : 2) {}\n" // don't simplify and verify this code
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int y = rand(), z = rand();\n"
" if (y || (!y && z));\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (style) Redundant condition: !y. 'y || (!y && z)' is equivalent to 'y || z'\n", errout.str());
check("void f() {\n"
" int y = rand(), z = rand();\n"
" if (y || !y && z);\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (style) Redundant condition: !y. 'y || (!y && z)' is equivalent to 'y || z'\n", errout.str());
check("void f() {\n"
" if (!a || a && b) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: a. '!a || (a && b)' is equivalent to '!a || b'\n", errout.str());
check("void f(const Token *tok) {\n"
" if (!tok->next()->function() || \n"
" (tok->next()->function() && tok->next()->function()->isConstructor()));\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: tok->next()->function(). '!A || (A && B)' is equivalent to '!A || B'\n", errout.str());
check("void f() {\n"
" if (!tok->next()->function() || \n"
" (!tok->next()->function() && tok->next()->function()->isConstructor()));\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" if (!tok->next()->function() || \n"
" (!tok2->next()->function() && tok->next()->function()->isConstructor()));\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(const Token *tok) {\n"
" if (!tok->next(1)->function(1) || \n"
" (tok->next(1)->function(1) && tok->next(1)->function(1)->isConstructor()));\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: tok->next(1)->function(1). '!A || (A && B)' is equivalent to '!A || B'\n", errout.str());
check("void f() {\n"
" if (!tok->next()->function(1) || \n"
" (tok->next()->function(2) && tok->next()->function()->isConstructor()));\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int y = rand(), z = rand();\n"
" if (y==0 || y!=0 && z);\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (style) Redundant condition: y!=0. 'y==0 || (y!=0 && z)' is equivalent to 'y==0 || z'\n", errout.str());
check("void f() {\n"
" if (x>0 || (x<0 && y)) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
// Test Token::expressionString, TODO move this test
check("void f() {\n"
" if (!dead || (dead && (*it).ticks > 0)) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: dead. '!dead || (dead && (*it).ticks>0)' is equivalent to '!dead || (*it).ticks>0'\n", errout.str());
check("void f() {\n"
" if (!x || (x && (2>(y-1)))) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Redundant condition: x. '!x || (x && 2>(y-1))' is equivalent to '!x || 2>(y-1)'\n", errout.str());
}
// clarify conditions with bitwise operator and comparison
void clarifyCondition2() {
check("void f() {\n"
" if (x & 3 == 2) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Suspicious condition (bitwise operator + comparison); Clarify expression with parentheses.\n"
"[test.cpp:2]: (style) Boolean result is used in bitwise operation. Clarify expression with parentheses.\n"
"[test.cpp:2]: (style) Condition 'x&3==2' is always false\n"
"[test.cpp:2]: (style) Condition '3==2' is always false\n", errout.str());
check("void f() {\n"
" if (a & fred1.x == fred2.y) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Suspicious condition (bitwise operator + comparison); Clarify expression with parentheses.\n"
"[test.cpp:2]: (style) Boolean result is used in bitwise operation. Clarify expression with parentheses.\n"
, errout.str());
}
// clarify condition that uses ! operator and then bitwise operator
void clarifyCondition3() {
check("void f(int w) {\n"
" if(!w & 0x8000) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Boolean result is used in bitwise operation. Clarify expression with parentheses.\n", errout.str());
check("void f(int w) {\n"
" if((!w) & 0x8000) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" if (x == foo() & 2) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Boolean result is used in bitwise operation. Clarify expression with parentheses.\n", errout.str());
check("void f() {\n"
" if (2 & x == foo()) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Boolean result is used in bitwise operation. Clarify expression with parentheses.\n", errout.str());
check("void f() {\n"
" if (2 & (x == foo())) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(std::list<int> &ints) { }");
ASSERT_EQUALS("", errout.str());
check("void f() { A<x &> a; }");
ASSERT_EQUALS("", errout.str());
check("void f() { a(x<y|z,0); }", "test.c"); // filename is c => there are never templates
ASSERT_EQUALS("[test.c:1]: (style) Boolean result is used in bitwise operation. Clarify expression with parentheses.\n", errout.str());
check("class A<B&,C>;", "test.cpp");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" if (result != (char *)&inline_result) { }\n" // don't simplify and verify cast
"}");
ASSERT_EQUALS("", errout.str());
// #8495
check("void f(bool a, bool b) {\n"
" C & a & b;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void clarifyCondition4() { // ticket #3110
check("typedef double SomeType;\n"
"typedef std::pair<std::string,SomeType> PairType;\n"
"struct S\n"
"{\n"
" bool operator()\n"
" ( PairType const & left\n"
" , PairType const & right) const\n"
" {\n"
" return left.first < right.first;\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void clarifyCondition5() { // ticket #3609 (using | in template instantiation)
check("template<bool B> struct CWinTraits;\n"
"CWinTraits<WS_CHILD|WS_VISIBLE>::GetWndStyle(0);");
ASSERT_EQUALS("", errout.str());
}
void clarifyCondition6() {
check("template<class Y>\n"
"SharedPtr& operator=( SharedPtr<Y> const & r ) {\n"
" px = r.px;\n"
" return *this;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void clarifyCondition7() {
// Ensure that binary and unary &, and & in declarations are distinguished properly
check("void f(bool error) {\n"
" bool & withoutSideEffects=found.first->second;\n" // Declaring a reference to a boolean; & is no operator at all
" execute(secondExpression, &programMemory, &result, &error);\n" // Unary &
"}");
ASSERT_EQUALS("", errout.str());
}
void clarifyCondition8() {
// don't warn when boolean result comes from function call, array index, etc
// the operator precedence is not unknown then
check("bool a();\n"
"bool f(bool b) {\n"
" return (a() & b);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("bool f(bool *a, bool b) {\n"
" return (a[10] & b);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("struct A { bool a; };\n"
"bool f(struct A a, bool b) {\n"
" return (a.a & b);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("struct A { bool a; };\n"
"bool f(struct A a, bool b) {\n"
" return (A::a & b);\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testBug5895() {
check("void png_parse(uint64_t init, int buf_size) {\n"
" if (init == 0x89504e470d0a1a0a || init == 0x8a4d4e470d0a1a0a)\n"
" ;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testBug5309() {
check("extern uint64_t value;\n"
"void foo() {\n"
" if( ( value >= 0x7ff0000000000001ULL )\n"
" && ( value <= 0x7fffffffffffffffULL ) );\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void alwaysTrue() {
check("void f() {\n" // #4842
" int x = 0;\n"
" if (a) { return; }\n" // <- this is just here to fool simplifyKnownVariabels
" if (!x) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (style) Condition '!x' is always true\n", errout.str());
check("bool f(int x) {\n"
" if(x == 0) { x++; return x == 0; } \n"
" return false;\n"
"}");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:2]: (style) Condition 'x==0' is always false\n", errout.str());
check("void f() {\n" // #6898 (Token::expressionString)
" int x = 0;\n"
" A(x++ == 1);\n"
" A(x++ == 2);\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (style) Condition 'x++==1' is always false\n"
"[test.cpp:4]: (style) Condition 'x++==2' is always false\n",
errout.str());
check("void f1(const std::string &s) { if(s.empty()) if(s.size() == 0) {}} ");
ASSERT_EQUALS("[test.cpp:1] -> [test.cpp:1]: (style) Condition 's.size()==0' is always true\n", errout.str());
check("void f() {\n"
" int buf[42];\n"
" if( buf != 0) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Condition 'buf!=0' is always true\n", errout.str()); // #8924
check("void f() {\n"
" int buf[42];\n"
" if( !buf ) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Condition '!buf' is always false\n", errout.str());
check("void f() {\n"
" int buf[42];\n"
" bool b = buf;\n"
" if( b ) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (style) Condition 'b' is always true\n", errout.str());
check("void f() {\n"
" int buf[42];\n"
" bool b = buf;\n"
" if( !b ) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (style) Condition '!b' is always false\n", errout.str());
check("void f() {\n"
" int buf[42];\n"
" int * p = nullptr;\n"
" if( buf == p ) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (style) Condition 'buf==p' is always false\n", errout.str());
check("void f(bool x) {\n"
" int buf[42];\n"
" if( buf || x ) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Condition 'buf' is always true\n", errout.str());
check("void f(int * p) {\n"
" int buf[42];\n"
" if( buf == p ) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int buf[42];\n"
" int p[42];\n"
" if( buf == p ) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int buf[42];\n"
" if( buf == 1) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// Avoid FP when condition comes from macro
check("#define NOT !\n"
"void f() {\n"
" int x = 0;\n"
" if (a) { return; }\n" // <- this is just here to fool simplifyKnownVariabels
" if (NOT x) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("#define M x != 0\n"
"void f() {\n"
" int x = 0;\n"
" if (a) { return; }\n" // <- this is just here to fool simplifyKnownVariabels
" if (M) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("#define IF(X) if (X && x())\n"
"void f() {\n"
" IF(1) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
// Avoid FP for sizeof condition
check("void f() {\n"
" if (sizeof(char) != 123) {}\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int x = 123;\n"
" if (sizeof(char) != x) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (style) Condition 'sizeof(char)!=x' is always true\n", errout.str());
// Don't warn in assertions. Condition is often 'always true' by intention.
// If platform,defines,etc cause an 'always false' assertion then that is not very dangerous neither
check("void f() {\n"
" int x = 0;\n"
" assert(x == 0);\n"
"}");
ASSERT_EQUALS("", errout.str());
// #7783 FP knownConditionTrueFalse on assert(0 && "message")
check("void foo(int x) {\n"
" if (x<0)\n"
" {\n"
" assert(0 && \"bla\");\n"
" ASSERT(0 && \"bla\");\n"
" assert_foo(0 && \"bla\");\n"
" ASSERT_FOO(0 && \"bla\");\n"
" assert((int)(0==0));\n"
" assert((int)(0==0) && \"bla\");\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #7750 char literals in boolean expressions
check("void f() {\n"
" if('a'){}\n"
" if(L'b'){}\n"
" if(1 && 'c'){}\n"
" int x = 'd' ? 1 : 2;\n"
"}");
ASSERT_EQUALS("", errout.str());
// Skip literals
check("void f() { if(true) {} }");
ASSERT_EQUALS("", errout.str());
check("void f() { if(false) {} }");
ASSERT_EQUALS("", errout.str());
check("void f() { if(!true) {} }");
ASSERT_EQUALS("", errout.str());
check("void f() { if(!false) {} }");
ASSERT_EQUALS("", errout.str());
check("void f() { if(0) {} }");
ASSERT_EQUALS("", errout.str());
check("void f() { if(1) {} }");
ASSERT_EQUALS("", errout.str());
check("void f(int i) {\n"
" bool b = false;\n"
" if (i == 0) b = true;\n"
" else if (!b && i == 1) {}\n"
" if (b)\n"
" {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (style) Condition '!b' is always true\n", errout.str());
check("bool f() { return nullptr; }");
ASSERT_EQUALS("", errout.str());
check("enum E { A };\n"
"bool f() { return A; }\n");
ASSERT_EQUALS("", errout.str());
check("bool f() { \n"
" const int x = 0;\n"
" return x; \n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int f(void){return 1/abs(10);}");
ASSERT_EQUALS("", errout.str());
check("bool f() { \n"
" int x = 0;\n"
" return x; \n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("bool f() {\n"
" const int a = 50;\n"
" const int b = 52;\n"
" return a+b;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int f() {\n"
" int a = 50;\n"
" int b = 52;\n"
" a++;\n"
" b++;\n"
" return a+b;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("bool& g();\n"
"bool f() {\n"
" bool & b = g();\n"
" b = false;\n"
" return b;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct A {\n"
" bool b;\n"
" bool f() {\n"
" b = false;\n"
" return b;\n"
" }\n"
"};\n");
ASSERT_EQUALS("", errout.str());
check("bool f(long maxtime) {\n"
" if (std::time(0) > maxtime)\n"
" return std::time(0) > maxtime;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void foo(double param) {\n"
" while(bar()) {\n"
" if (param<0.)\n"
" return;\n"
" }\n"
" if (param<0.)\n"
" return;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void foo(int i) {\n"
" if (i==42)\n"
" {\n"
" bar();\n"
" }\n"
" if (cond && (42==i))\n"
" return;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// 8842 crash
check("class a {\n"
" int b;\n"
" c(b);\n"
" void f() {\n"
" if (b) return;\n"
" }\n"
"};\n");
ASSERT_EQUALS("", errout.str());
check("void f(const char* x, const char* t) {\n"
" if (!(strcmp(x, y) == 0)) { return; }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(const int a[]){ if (a == 0){} }");
ASSERT_EQUALS("", errout.str());
check("struct S {\n"
" bool operator<(const S&);\n"
"};\n"
"int main() {\n"
" S s;\n"
" bool c = s<s;\n"
" if (c) return 0;\n"
" else return 42;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("long X::g(bool unknown, int& result) {\n"
" long ret = 0;\n"
" bool f = false;\n"
" f = f || unknown;\n"
" f ? result = 42 : ret = -1;\n"
" return ret;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int f(void *handle) {\n"
" if (!handle) return 0;\n"
" if (handle) return 1;\n"
" else return 0;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Condition 'handle' is always true\n", errout.str());
check("int f(void *handle) {\n"
" if (handle == 0) return 0;\n"
" if (handle) return 1;\n"
" else return 0;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Condition 'handle' is always true\n", errout.str());
check("int f(void *handle) {\n"
" if (handle != 0) return 0;\n"
" if (handle) return 1;\n"
" else return 0;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Condition 'handle' is always false\n", errout.str());
check("void f(void* x, void* y) {\n"
" if (x == nullptr && y == nullptr)\n"
" return;\n"
" if (x == nullptr || y == nullptr)\n"
" return;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void* g();\n"
"void f(void* a, void* b) {\n"
" while (a) {\n"
" a = g();\n"
" if (a == b)\n"
" break;\n"
" }\n"
" if (a) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void* g();\n"
"void f(void* a, void* b) {\n"
" while (a) {\n"
" a = g();\n"
" }\n"
" if (a) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:6]: (style) Condition 'a' is always false\n", errout.str());
check("void f(int * x, bool b) {\n"
" if (!x && b) {}\n"
" else if (x) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" const std::string x=\"xyz\";\n"
" if(!x.empty()){}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Condition '!x.empty()' is always true\n", errout.str());
check("std::string g();\n"
"void f() {\n"
" const std::string msg = g();\n"
" if(!msg.empty()){}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(int *array, int size ) {\n"
" for(int i = 0; i < size; ++i) {\n"
" if(array == 0)\n"
" continue;\n"
" if(array){}\n"
" }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:5]: (style) Condition 'array' is always true\n", errout.str());
check("void f(int *array, int size ) {\n"
" for(int i = 0; i < size; ++i) {\n"
" if(array == 0)\n"
" continue;\n"
" else if(array){}\n"
" }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:5]: (style) Condition 'array' is always true\n", errout.str());
// #9277
check("int f() {\n"
" constexpr bool x = true;\n"
" if constexpr (x)\n"
" return 0;\n"
" else\n"
" return 1;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #9319
check("struct S {\n"
" int a;\n"
" int b;\n"
"};\n"
"void g(S s, bool& x);\n"
"void f() {\n"
" bool x = false;\n"
" g({0, 1}, x);\n"
" if (x) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #9318
check("class A {};\n"
"class B : public A {};\n"
"void f(A* x) {\n"
" if (!x)\n"
" return;\n"
" auto b = dynamic_cast<B*>(x);\n"
" if (b) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// handleKnownValuesInLoop
check("bool g();\n"
"void f(bool x) {\n"
" if (x) while(x) x = g();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// isLikelyStream
check("void f(std::istringstream& iss) {\n"
" std::string x;\n"
" while (iss) {\n"
" iss >> x;\n"
" if (!iss) break;\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if (x > 5) {\n"
" x++;\n"
" if (x == 1) {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (style) Condition 'x==1' is always false\n", errout.str());
check("void f(int x) {\n"
" if (x > 5) {\n"
" x++;\n"
" if (x != 1) {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:4]: (style) Condition 'x!=1' is always true\n", errout.str());
// #9332
check("struct A { void* g(); };\n"
"void f() {\n"
" A a;\n"
" void* b = a.g();\n"
" if (!b) return;\n"
" void* c = a.g();\n"
" if (!c) return;\n"
" bool compare = c == b;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #9361
check("void f(char c) {\n"
" if (c == '.') {}\n"
" else if (isdigit(c) != 0) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #9351
check("int f(int x) {\n"
" const bool b = x < 42;\n"
" if(b) return b?0:-1;\n"
" return 42;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:3]: (style) Condition 'b' is always true\n", errout.str());
// #9362
check("uint8_t g();\n"
"void f() {\n"
" const uint8_t v = g();\n"
" if((v != 0x00)) {\n"
" if( (v & 0x01) == 0x00) {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void alwaysTrueContainer() {
// #9329
check("void c1(std::vector<double>&);\n"
"void c2(std::vector<double>&);\n"
"void foo(int flag) {\n"
" std::vector<double> g;\n"
" if (flag)\n"
" c1(g );\n"
" else\n"
" c2(g );\n"
" if ( !g.empty() )\n"
" return;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void foo(int flag) {\n"
" std::vector<double> g;\n"
" if (flag)\n"
" c1(g );\n"
" else\n"
" c2(g );\n"
" if ( !g.empty() )\n"
" return;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void multiConditionAlwaysTrue() {
check("void f() {\n"
" int val = 0;\n"
" if (val < 0) continue;\n"
" if (val > 0) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int val = 0;\n"
" if (val < 0) {\n"
" if (val > 0) {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int val = 0;\n"
" if (val < 0) {\n"
" if (val < 0) {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int activate = 0;\n"
" int foo = 0;\n"
" if (activate) {}\n"
" else if (foo) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (style) Condition 'activate' is always false\n"
"[test.cpp:5]: (style) Condition 'foo' is always false\n", errout.str());
// #6904
check("void f() {\n"
" const int b[2] = { 1,0 };\n"
" if(b[1] == 2) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (style) Condition 'b[1]==2' is always false\n", errout.str());
}
void duplicateCondition() {
check("void f(bool x) {\n"
" if(x) {}\n"
" if(x) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) The if condition is the same as the previous if condition\n",
errout.str());
check("void f(int x) {\n"
" if(x == 1) {}\n"
" if(x == 1) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) The if condition is the same as the previous if condition\n",
errout.str());
check("void f(int x) {\n"
" if(x == 1) {}\n"
" if(x == 2) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if(x == 1) {}\n"
" if(x != 1) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(bool x) {\n"
" if(x) {}\n"
" g();\n"
" if(x) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(int x) {\n"
" if(x == 1) { x++; }\n"
" if(x == 1) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #8996
check("void g(int** v);\n"
"void f() {\n"
" int a = 0;\n"
" int b = 0;\n"
" int* d[] = {&a, &b};\n"
" g(d);\n"
" if (a) {}\n"
" if (b) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #9311
check("struct c {\n"
" int* p;\n"
"};\n"
"void g(struct c* v);\n"
"void f() {\n"
" int a = 0;\n"
" int b = 0;\n"
" struct c d[] = {{&a}, {&b}};\n"
" g(d);\n"
" if (a) {}\n"
" if (b) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #8993
check("void f(const std::string& x) {\n"
" auto y = x;\n"
" if (x.empty()) y = \"1\";\n"
" if (y.empty()) return;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void checkInvalidTestForOverflow() {
check("void f(char *p, unsigned int x) {\n"
" assert((p + x) < p);\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Invalid test for overflow '(p+x)<p'. Condition is always false unless there is overflow, and overflow is undefined behaviour.\n", errout.str());
check("void f(char *p, unsigned int x) {\n"
" assert((p + x) >= p);\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Invalid test for overflow '(p+x)>=p'. Condition is always true unless there is overflow, and overflow is undefined behaviour.\n", errout.str());
check("void f(char *p, unsigned int x) {\n"
" assert(p > (p + x));\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Invalid test for overflow 'p>(p+x)'. Condition is always false unless there is overflow, and overflow is undefined behaviour.\n", errout.str());
check("void f(char *p, unsigned int x) {\n"
" assert(p <= (p + x));\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Invalid test for overflow 'p<=(p+x)'. Condition is always true unless there is overflow, and overflow is undefined behaviour.\n", errout.str());
check("void f(signed int x) {\n"
" assert(x + 100 < x);\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Invalid test for overflow 'x+100<x'. Condition is always false unless there is overflow, and overflow is undefined behaviour.\n", errout.str());
check("void f(signed int x) {\n" // unsigned overflow => don't warn
" assert(x + 100U < x);\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void checkConditionIsAlwaysTrueOrFalseInsideIfWhile() {
check("void f() {\n"
" enum states {A,B,C};\n"
" const unsigned g_flags = B|C;\n"
" if(g_flags & A) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (style) Condition 'g_flags&A' is always false\n", errout.str());
check("void f() {\n"
" int a = 5;"
" if(a) {}\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Condition 'a' is always true\n", errout.str());
check("void f() {\n"
" int a = 5;"
" while(a + 1) { a--; }\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" int a = 5;"
" while(a + 1) { return; }\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Condition 'a+1' is always true\n", errout.str());
}
void alwaysTrueFalseInLogicalOperators() {
check("bool f();\n"
"void foo() { bool x = true; if(x||f()) {}}\n");
ASSERT_EQUALS("[test.cpp:2]: (style) Condition 'x' is always true\n", errout.str());
check("void foo(bool b) { bool x = true; if(x||b) {}}\n");
ASSERT_EQUALS("[test.cpp:1]: (style) Condition 'x' is always true\n", errout.str());
check("void foo(bool b) { if(true||b) {}}\n");
ASSERT_EQUALS("", errout.str());
check("bool f();\n"
"void foo() { bool x = false; if(x||f()) {}}\n");
ASSERT_EQUALS("[test.cpp:2]: (style) Condition 'x' is always false\n", errout.str());
check("bool f();\n"
"void foo() { bool x = false; if(x&&f()) {}}\n");
ASSERT_EQUALS("[test.cpp:2]: (style) Condition 'x' is always false\n", errout.str());
check("void foo(bool b) { bool x = false; if(x&&b) {}}\n");
ASSERT_EQUALS("[test.cpp:1]: (style) Condition 'x' is always false\n", errout.str());
check("void foo(bool b) { if(false&&b) {}}\n");
ASSERT_EQUALS("", errout.str());
check("bool f();\n"
"void foo() { bool x = true; if(x&&f()) {}}\n");
ASSERT_EQUALS("[test.cpp:2]: (style) Condition 'x' is always true\n", errout.str());
}
void pointerAdditionResultNotNull() {
check("void f(char *ptr) {\n"
" if (ptr + 1 != 0);\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Comparison is wrong. Result of 'ptr+1' can't be 0 unless there is pointer overflow, and pointer overflow is undefined behaviour.\n", errout.str());
}
void duplicateConditionalAssign() {
setMultiline();
check("void f(int& x, int y) {\n"
" if (x == y)\n"
" x = y;\n"
"}\n");
ASSERT_EQUALS("test.cpp:3:style:Assignment 'x=y' is redundant with condition 'x==y'.\n"
"test.cpp:2:note:Condition 'x==y'\n"
"test.cpp:3:note:Assignment 'x=y' is redundant\n", errout.str());
check("void f(int& x, int y) {\n"
" if (x != y)\n"
" x = y;\n"
"}\n");
ASSERT_EQUALS("test.cpp:2:style:The statement 'if (x!=y) x=y' is logically equivalent to 'x=y'.\n"
"test.cpp:3:note:Assignment 'x=y'\n"
"test.cpp:2:note:Condition 'x!=y' is redundant\n", errout.str());
check("void f(int& x, int y) {\n"
" if (x == y)\n"
" x = y;\n"
" else\n"
" x = 1;\n"
"}\n");
ASSERT_EQUALS("test.cpp:3:style:Assignment 'x=y' is redundant with condition 'x==y'.\n"
"test.cpp:2:note:Condition 'x==y'\n"
"test.cpp:3:note:Assignment 'x=y' is redundant\n", errout.str());
check("void f(int& x, int y) {\n"
" if (x != y)\n"
" x = y;\n"
" else\n"
" x = 1;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(int& x, int y) {\n"
" if (x == y)\n"
" x = y + 1;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void g();\n"
"void f(int& x, int y) {\n"
" if (x == y) {\n"
" x = y;\n"
" g();\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
};
REGISTER_TEST(TestCondition)
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