/*
* 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 .
*/
#include "checkautovariables.h"
#include "settings.h"
#include "testsuite.h"
#include "tokenize.h"
class TestAutoVariables : public TestFixture {
public:
TestAutoVariables() : TestFixture("TestAutoVariables") {
}
private:
Settings settings;
void check(const char code[], bool inconclusive = false, const char* filename = "test.cpp") {
// Clear the error buffer..
errout.str("");
settings.inconclusive = inconclusive;
// Tokenize..
Tokenizer tokenizer(&settings, this);
std::istringstream istr(code);
tokenizer.tokenize(istr, filename);
CheckAutoVariables checkAutoVariables;
checkAutoVariables.runChecks(&tokenizer, &settings, this);
}
void run() OVERRIDE {
settings.addEnabled("warning");
settings.addEnabled("style");
LOAD_LIB_2(settings.library, "std.cfg");
TEST_CASE(testautovar1);
TEST_CASE(testautovar2);
TEST_CASE(testautovar3); // ticket #2925
TEST_CASE(testautovar4); // ticket #2928
TEST_CASE(testautovar5); // ticket #2926
TEST_CASE(testautovar6); // ticket #2931
TEST_CASE(testautovar7); // ticket #3066
TEST_CASE(testautovar8);
TEST_CASE(testautovar9);
TEST_CASE(testautovar10); // ticket #2930 - void f(char *p) { p = '\0'; }
TEST_CASE(testautovar11); // ticket #4641 - fp, assign local struct member address to function parameter
TEST_CASE(testautovar12); // ticket #5024 - crash
TEST_CASE(testautovar13); // ticket #5537 - crash
TEST_CASE(testautovar14); // ticket #4776 - assignment of function parameter, goto
TEST_CASE(testautovar15); // ticket #6538
TEST_CASE(testautovar16); // ticket #8114
TEST_CASE(testautovar_array1);
TEST_CASE(testautovar_array2);
TEST_CASE(testautovar_normal); // "normal" token list that does not remove casts etc
TEST_CASE(testautovar_ptrptr); // ticket #6956
TEST_CASE(testautovar_return1);
TEST_CASE(testautovar_return2);
TEST_CASE(testautovar_return3);
TEST_CASE(testautovar_return4);
TEST_CASE(testautovar_extern);
TEST_CASE(testinvaliddealloc);
TEST_CASE(testinvaliddealloc_C);
TEST_CASE(testassign1); // Ticket #1819
TEST_CASE(testassign2); // Ticket #2765
TEST_CASE(assignAddressOfLocalArrayToGlobalPointer);
TEST_CASE(assignAddressOfLocalVariableToGlobalPointer);
TEST_CASE(assignAddressOfLocalVariableToMemberVariable);
TEST_CASE(returnLocalVariable1);
TEST_CASE(returnLocalVariable2);
TEST_CASE(returnLocalVariable3); // &x[0]
TEST_CASE(returnLocalVariable4); // x+y
TEST_CASE(returnLocalVariable5); // cast
TEST_CASE(returnLocalVariable6); // valueflow
// return reference..
TEST_CASE(returnReference1);
TEST_CASE(returnReference2);
TEST_CASE(returnReference3);
TEST_CASE(returnReference4);
TEST_CASE(returnReference5);
TEST_CASE(returnReference6);
TEST_CASE(returnReference7);
TEST_CASE(returnReferenceFunction);
TEST_CASE(returnReferenceContainer);
TEST_CASE(returnReferenceLiteral);
TEST_CASE(returnReferenceCalculation);
TEST_CASE(returnReferenceLambda);
TEST_CASE(returnReferenceInnerScope);
TEST_CASE(returnReferenceRecursive);
TEST_CASE(danglingReference);
// global namespace
TEST_CASE(testglobalnamespace);
TEST_CASE(returnParameterAddress);
TEST_CASE(testconstructor); // ticket #5478 - crash
TEST_CASE(variableIsUsedInScope); // ticket #5599 crash in variableIsUsedInScope()
TEST_CASE(danglingLifetimeLambda);
TEST_CASE(danglingLifetimeContainer);
TEST_CASE(danglingLifetime);
TEST_CASE(danglingLifetimeFunction);
TEST_CASE(danglingLifetimeAggegrateConstructor);
TEST_CASE(danglingLifetimeInitList);
TEST_CASE(danglingLifetimeImplicitConversion);
TEST_CASE(invalidLifetime);
TEST_CASE(deadPointer);
}
void testautovar1() {
check("void func1(int **res)\n"
"{\n"
" int num = 2;\n"
" *res = #\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
check("void func1(int **res)\n"
"{\n"
" int num = 2;\n"
" res = #\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (warning) Assignment of function parameter has no effect outside the function. Did you forget dereferencing it?\n", errout.str());
check("void func1(int **res)\n"
"{\n"
" int num = 2;\n"
" foo.res = #\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testautovar2() {
check("class Fred {\n"
" void func1(int **res);\n"
"}\n"
"void Fred::func1(int **res)\n"
"{\n"
" int num = 2;\n"
" *res = #\n"
"}");
ASSERT_EQUALS("[test.cpp:7]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
check("class Fred {\n"
" void func1(int **res);\n"
"}\n"
"void Fred::func1(int **res)\n"
"{\n"
" int num = 2;\n"
" res = #\n"
"}");
ASSERT_EQUALS("[test.cpp:7]: (warning) Assignment of function parameter has no effect outside the function. Did you forget dereferencing it?\n", errout.str());
check("class Fred {\n"
" void func1(int **res);\n"
"}\n"
"void Fred::func1(int **res)\n"
"{\n"
" int num = 2;\n"
" foo.res = #\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testautovar3() { // ticket #2925
check("void foo(int **p)\n"
"{\n"
" int x[100];\n"
" *p = x;\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
}
void testautovar4() { // ticket #2928
check("void foo(int **p)\n"
"{\n"
" static int x[100];\n"
" *p = x;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testautovar5() { // ticket #2926
check("void foo(struct AB *ab)\n"
"{\n"
" char a;\n"
" ab->a = &a;\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
}
void testautovar6() { // ticket #2931
check("void foo(struct X *x)\n"
"{\n"
" char a[10];\n"
" x->str = a;\n"
"}", false);
ASSERT_EQUALS("", errout.str());
check("void foo(struct X *x)\n"
"{\n"
" char a[10];\n"
" x->str = a;\n"
"}", true);
ASSERT_EQUALS("[test.cpp:4]: (error, inconclusive) Address of local auto-variable assigned to a function parameter.\n", errout.str());
}
void testautovar7() { // ticket #3066
check("struct txt_scrollpane_s * TXT_NewScrollPane(struct txt_widget_s * target)\n"
"{\n"
" struct txt_scrollpane_s * scrollpane;\n"
" target->parent = &scrollpane->widget;\n"
" return scrollpane;\n"
"}", false);
ASSERT_EQUALS("", errout.str());
}
void testautovar8() {
check("void foo(int*& p) {\n"
" int i = 0;\n"
" p = &i;\n"
"}", false);
ASSERT_EQUALS("[test.cpp:3]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
check("void foo(std::string& s) {\n"
" s = foo;\n"
"}", false);
ASSERT_EQUALS("", errout.str());
}
void testautovar9() {
check("struct FN {int i;};\n"
"struct FP {FN* f};\n"
"void foo(int*& p, FN* p_fp) {\n"
" FN fn;\n"
" FP fp;\n"
" p = &fn.i;\n"
" p = &p_fp->i;\n"
" p = &fp.f->i;\n"
"}", false);
ASSERT_EQUALS("[test.cpp:6]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
}
void testautovar10() { // #2930 - assignment of function parameter
check("void foo(char* p) {\n"
" p = 0;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Assignment of function parameter has no effect outside the function. Did you forget dereferencing it?\n", errout.str());
check("void foo(int b) {\n"
" b = foo(b);\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Assignment of function parameter has no effect outside the function.\n", errout.str());
check("void foo(int b) {\n"
" b += 1;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Assignment of function parameter has no effect outside the function.\n", errout.str());
check("void foo(std::string s) {\n"
" s = foo(b);\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (style) Assignment of function parameter has no effect outside the function.\n", errout.str());
check("void foo(char* p) {\n" // don't warn for self assignment, there is another warning for this
" p = p;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void foo(char* p) {\n"
" if (!p) p = buf;\n"
" *p = 0;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void foo(char* p) {\n"
" if (!p) p = buf;\n"
" do_something(p);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void foo(char* p) {\n"
" while (!p) p = buf;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void foo(char* p) {\n"
" p = 0;\n"
" asm(\"somecmd\");\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void foo(Foo* p) {\n"
" p = 0;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Assignment of function parameter has no effect outside the function. Did you forget dereferencing it?\n", errout.str());
check("class Foo {};\n"
"void foo(Foo p) {\n"
" p = 0;\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (style) Assignment of function parameter has no effect outside the function.\n", errout.str());
check("void foo(Foo p) {\n"
" p = 0;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void foo(int& p) {\n"
" p = 0;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("double foo(double d) {\n" // #5005
" int i = d;\n"
" d = i;\n"
" return d;"
"}",false);
ASSERT_EQUALS("", errout.str());
check("void foo(int* ptr) {\n" // #4793
" ptr++;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Assignment of function parameter has no effect outside the function. Did you forget dereferencing it?\n", errout.str());
check("void foo(int* ptr) {\n" // #3177
" --ptr;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Assignment of function parameter has no effect outside the function. Did you forget dereferencing it?\n", errout.str());
check("void foo(struct S* const x) {\n" // #7839
" ++x->n;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testautovar11() { // #4641 - fp, assign local struct member address to function parameter
check("struct A {\n"
" char (*data)[10];\n"
"};\n"
"void foo(char** p) {\n"
" struct A a = bar();\n"
" *p = &(*a.data)[0];\n"
"}");
ASSERT_EQUALS("", errout.str());
check("struct A {\n"
" char data[10];\n"
"};\n"
"void foo(char** p) {\n"
" struct A a = bar();\n"
" *p = &a.data[0];\n"
"}");
ASSERT_EQUALS("[test.cpp:6]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
check("void f(char **out) {\n"
" struct S *p = glob;\n"
" *out = &p->data;\n"
"}");
ASSERT_EQUALS("", errout.str());
// #4998
check("void f(s8**out) {\n"
" s8 *p;\n" // <- p is pointer => no error
" *out = &p[1];\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f(s8**out) {\n"
" s8 p[10];\n" // <- p is array => error
" *out = &p[1];\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
}
void testautovar12() { // Ticket #5024, #5050 - Crash on invalid input
ASSERT_THROW(check("void f(int* a) { a = }"), InternalError);
check("struct custom_type { custom_type(int) {} };\n"
"void func(int) {}\n"
"int var;\n"
"void init() { func(var); }\n"
"UNKNOWN_MACRO_EXPANDING_TO_SIGNATURE { custom_type a(var); }");
}
void testautovar13() { // Ticket #5537
check("class FileManager {\n"
" FileManager() : UniqueRealDirs(*new UniqueDirContainer())\n"
" {}\n"
" ~FileManager() {\n"
" delete &UniqueRealDirs;\n"
" }\n"
"};\n");
}
void testautovar14() { // Ticket #4776
check("void f(int x) {\n"
"label:"
" if (x>0) {\n"
" x = x >> 1;\n"
" goto label;\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testautovar15() { // Ticket #6538
check("static const float4 darkOutline(0.05f, 0.05f, 0.05f, 0.95f);\n"
"static const float darkLuminosity = 0.05 +\n"
" 0.0722f * math::powf(darkOutline[2], 2.2);\n"
"const float4* ChooseOutlineColor(const float4& textColor) {\n"
" const float lumdiff = something;\n"
" if (lumdiff > 5.0f)\n"
" return &darkOutline;\n"
" return 0;\n"
"}", false);
ASSERT_EQUALS("", errout.str());
}
void testautovar16() { // Ticket #8114
check("void f(const void* ptr, bool* result) {\n"
" int dummy;\n"
" *result = (&dummy < ptr);\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testautovar_array1() {
check("void func1(int* arr[2])\n"
"{\n"
" int num=2;"
" arr[0]=#\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
}
void testautovar_array2() {
check("class Fred {\n"
" void func1(int* arr[2]);\n"
"}\n"
"void Fred::func1(int* arr[2])\n"
"{\n"
" int num=2;"
" arr[0]=#\n"
"}");
ASSERT_EQUALS("[test.cpp:6]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
}
void testautovar_normal() {
check("void f(XmDestinationCallbackStruct *ds)\n"
"{\n"
" XPoint DropPoint;\n"
" ds->location_data = (XtPointer *)&DropPoint;\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
}
void testautovar_ptrptr() { // #6596
check("void remove_duplicate_matches (char **matches) {\n"
" char dead_slot;\n"
" matches[0] = (char *)&dead_slot;\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) Address of local auto-variable assigned to a function parameter.\n", errout.str());
}
void testautovar_return1() {
check("int* func1()\n"
"{\n"
" int num=2;"
" return #"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:3] -> [test.cpp:3]: (error) Returning pointer to local variable 'num' that will be invalid when returning.\n", errout.str());
}
void testautovar_return2() {
check("class Fred {\n"
" int* func1();\n"
"}\n"
"int* Fred::func1()\n"
"{\n"
" int num=2;"
" return #"
"}");
ASSERT_EQUALS("[test.cpp:6] -> [test.cpp:6] -> [test.cpp:6]: (error) Returning pointer to local variable 'num' that will be invalid when returning.\n", errout.str());
}
void testautovar_return3() {
// #2975 - FP
check("void** f()\n"
"{\n"
" void *&value = tls[id];"
" return &value;"
"}");
ASSERT_EQUALS("", errout.str());
}
void testautovar_return4() {
// #8058 - FP ignore return in lambda
check("void foo() {\n"
" int cond2;\n"
" dostuff([&cond2]() { return &cond2; });\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testautovar_extern() {
check("struct foo *f()\n"
"{\n"
" extern struct foo f;\n"
" return &f;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testinvaliddealloc() {
check("void func1() {\n"
" char tmp1[256];\n"
" free(tmp1);\n"
" char tmp2[256];\n"
" delete tmp2;\n"
" char tmp3[256];\n"
" delete tmp3;\n"
" char tmp4[256];\n"
" delete[] (tmp4);\n"
" char tmp5[256];\n"
" delete[] tmp5;\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) Deallocation of an auto-variable results in undefined behaviour.\n"
"[test.cpp:5]: (error) Deallocation of an auto-variable results in undefined behaviour.\n"
"[test.cpp:7]: (error) Deallocation of an auto-variable results in undefined behaviour.\n"
"[test.cpp:9]: (error) Deallocation of an auto-variable results in undefined behaviour.\n"
"[test.cpp:11]: (error) Deallocation of an auto-variable results in undefined behaviour.\n", errout.str());
check("void func1() {\n"
" char* tmp1[256];\n"
" init(tmp1);\n"
" delete tmp1[34];\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void func1() {\n"
" static char tmp1[256];\n"
" char *p = tmp1;\n"
" free(p);\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (error) Deallocation of an static variable (tmp1) results in undefined behaviour.\n", errout.str());
check("char tmp1[256];\n"
"void func1() {\n"
" char *p; if (x) p = tmp1;\n"
" free(p);\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (error) Deallocation of an global variable (tmp1) results in undefined behaviour.\n", errout.str());
check("void f()\n"
"{\n"
" char psz_title[10];\n"
" {\n"
" char *psz_title = 0;\n"
" abc(0, psz_title);\n"
" free(psz_title);\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
// #2298 new check: passing stack-address to free()
check("int main() {\n"
" int *p = malloc(4);\n"
" free(&p);\n"
" return 0;\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) Deallocation of an auto-variable results in undefined behaviour.\n", errout.str());
check("int main() {\n"
" int i;\n"
" free(&i);\n"
" return 0;\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) Deallocation of an auto-variable results in undefined behaviour.\n", errout.str());
// #5732
check("int main() {\n"
" long (*pKoeff)[256] = new long[9][256];\n"
" delete[] pKoeff;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("int main() {\n"
" long *pKoeff[256];\n"
" delete[] pKoeff;\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) Deallocation of an auto-variable results in undefined behaviour.\n", errout.str());
check("int main() {\n"
" long *pKoeff[256];\n"
" free (pKoeff);\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) Deallocation of an auto-variable results in undefined behaviour.\n", errout.str());
check("void foo() {\n"
" const intPtr& intref = Getter();\n"
" delete intref;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void test() {\n"
" MyObj& obj = *new MyObj;\n"
" delete &obj;\n"
"}");
ASSERT_EQUALS("", errout.str());
// #6506
check("struct F {\n"
" void free(void*) {}\n"
"};\n"
"void foo() {\n"
" char c1[1];\n"
" F().free(c1);\n"
" char *c2 = 0;\n"
" F().free(&c2);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("class foo {\n"
" void free(void* );\n"
" void someMethod() {\n"
" char **dst_copy = NULL;\n"
" free(&dst_copy);\n"
" }\n"
"};");
ASSERT_EQUALS("", errout.str());
// #6551
check("bool foo( ) {\n"
" SwTxtFld * pTxtFld = GetFldTxtAttrAt();\n"
" delete static_cast(&pTxtFld->GetAttr());\n"
"}");
ASSERT_EQUALS("", errout.str());
// #8910
check("void f() {\n"
" char stack[512];\n"
" RGNDATA *data;\n"
" if (data_size > sizeof (stack)) data = malloc (data_size);\n"
" else data = (RGNDATA *)stack;\n"
" if ((char *)data != stack) free (data);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void testinvaliddealloc_C() {
// #5691
check("void svn_repos_dir_delta2() {\n"
" struct context c;\n"
" SVN_ERR(delete(&c, root_baton, src_entry, pool));\n"
"}\n", false, "test.c");
ASSERT_EQUALS("", errout.str());
}
void testassign1() { // Ticket #1819
check("void f(EventPtr *eventP, ActionPtr **actionsP) {\n"
" EventPtr event = *eventP;\n"
" *actionsP = &event->actions;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void testassign2() { // Ticket #2765
check("static void function(unsigned long **datap) {\n"
" struct my_s *mr = global_structure_pointer;\n"
" *datap = &mr->value;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void assignAddressOfLocalArrayToGlobalPointer() {
check("int *p;\n"
"void f() {\n"
" int x[10];\n"
" p = x;\n"
"}");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:3] -> [test.cpp:4]: (error) Non-local variable 'p' will use pointer to local variable 'x'.\n", errout.str());
check("int *p;\n"
"void f() {\n"
" int x[10];\n"
" p = x;\n"
" p = 0;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void assignAddressOfLocalVariableToGlobalPointer() {
check("int *p;\n"
"void f() {\n"
" int x;\n"
" p = &x;\n"
"}");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:3] -> [test.cpp:4]: (error) Non-local variable 'p' will use pointer to local variable 'x'.\n", errout.str());
check("int *p;\n"
"void f() {\n"
" int x;\n"
" p = &x;\n"
" p = 0;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void assignAddressOfLocalVariableToMemberVariable() {
check("struct A {\n"
" void f() {\n"
" int x;\n"
" ptr = &x;\n"
" }\n"
" int *ptr;\n"
"};\n");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:3] -> [test.cpp:4]: (error) Non-local variable 'ptr' will use pointer to local variable 'x'.\n", errout.str());
check("struct A {\n"
" void f() {\n"
" int x;\n"
" ptr = &x;\n"
" ptr = 0;\n"
" }\n"
" int *ptr;\n"
"};\n");
ASSERT_EQUALS("", errout.str());
}
void returnLocalVariable1() {
check("char *foo()\n"
"{\n"
" char str[100] = {0};\n"
" return str;\n"
"}");
ASSERT_EQUALS(
"[test.cpp:4] -> [test.cpp:3] -> [test.cpp:4]: (error) Returning pointer to local variable 'str' that will be invalid when returning.\n",
errout.str());
check("char *foo()\n" // use ValueFlow
"{\n"
" char str[100] = {0};\n"
" char *p = str;\n"
" return p;\n"
"}");
ASSERT_EQUALS(
"[test.cpp:4] -> [test.cpp:3] -> [test.cpp:5]: (error) Returning pointer to local variable 'str' that will be invalid when returning.\n",
errout.str());
check("class Fred {\n"
" char *foo();\n"
"};\n"
"char *Fred::foo()\n"
"{\n"
" char str[100] = {0};\n"
" return str;\n"
"}");
ASSERT_EQUALS(
"[test.cpp:7] -> [test.cpp:6] -> [test.cpp:7]: (error) Returning pointer to local variable 'str' that will be invalid when returning.\n",
errout.str());
check("char * format_reg(char *outbuffer_start) {\n"
" return outbuffer_start;\n"
"}\n"
"void print_with_operands() {\n"
" char temp[42];\n"
" char *tp = temp;\n"
" tp = format_reg(tp);\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnLocalVariable2() {
check("std::string foo()\n"
"{\n"
" char str[100] = {0};\n"
" return str;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("class Fred {\n"
" std::string foo();\n"
"};\n"
"std::string Fred::foo()\n"
"{\n"
" char str[100] = {0};\n"
" return str;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnLocalVariable3() { // &x[..]
// #3030
check("char *foo() {\n"
" char q[] = \"AAAAAAAAAAAA\";\n"
" return &q[1];\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning pointer to local variable 'q' that will be invalid when returning.\n", errout.str());
check("char *foo()\n"
"{\n"
" static char q[] = \"AAAAAAAAAAAA\";\n"
" return &q[1];\n"
"}");
ASSERT_EQUALS("", errout.str());
check("char *foo()\n"
"{\n"
"char q[] = \"AAAAAAAAAAAA\";\n"
"char *p;\n"
"p = &q[1];\n"
"return p;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:3] -> [test.cpp:6]: (error) Returning pointer to local variable 'q' that will be invalid when returning.\n", errout.str());
}
void returnLocalVariable4() { // x+y
check("char *foo() {\n"
" char x[10] = {0};\n"
" return x+5;\n"
"}");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning pointer to local variable 'x' that will be invalid when returning.\n",
errout.str());
check("char *foo(int y) {\n"
" char x[10] = {0};\n"
" return (x+8)-y;\n"
"}");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning pointer to local variable 'x' that will be invalid when returning.\n",
errout.str());
}
void returnLocalVariable5() { // cast
check("char *foo() {\n"
" int x[10] = {0};\n"
" return (char *)x;\n"
"}");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning pointer to local variable 'x' that will be invalid when returning.\n",
errout.str());
}
void returnLocalVariable6() { // valueflow
check("int *foo() {\n"
" int x = 123;\n"
" int p = &x;\n"
" return p;\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'x' that will be invalid when returning.\n", errout.str());
}
void returnReference1() {
check("int &foo()\n"
"{\n"
" int s = 0;\n"
" int& x = s;\n"
" return x;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:5]: (error) Reference to local variable returned.\n", errout.str());
check("std::string &foo()\n"
"{\n"
" std::string s;\n"
" return s;\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (error) Reference to local variable returned.\n", errout.str());
check("std::vector &foo()\n"
"{\n"
" std::vector v;\n"
" return v;\n"
"}");
ASSERT_EQUALS("[test.cpp:4]: (error) Reference to local variable returned.\n", errout.str());
check("std::vector &foo()\n"
"{\n"
" static std::vector v;\n"
" return v;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("std::vector &foo()\n"
"{\n"
" thread_local std::vector v;\n"
" return v;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("std::string hello()\n"
"{\n"
" return \"hello\";\n"
"}\n"
"\n"
"std::string &f()\n"
"{\n"
" return hello();\n"
"}");
ASSERT_EQUALS("[test.cpp:8]: (error) Reference to temporary returned.\n", errout.str());
// make sure scope is used in function lookup
check("class Fred {\n"
" std::string hello() {\n"
" return std::string();\n"
" }\n"
"};\n"
"std::string &f() {\n"
" return hello();\n"
"}");
ASSERT_EQUALS("", errout.str());
check("std::string hello() {\n"
" return std::string();\n"
"}\n"
"\n"
"std::string &f() {\n"
" return hello();\n"
"}");
ASSERT_EQUALS("[test.cpp:6]: (error) Reference to temporary returned.\n", errout.str());
check("std::string hello() {\n"
" return \"foo\";\n"
"}\n"
"\n"
"std::string &f() {\n"
" return hello().substr(1);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("class Foo;\n"
"Foo hello() {\n"
" return Foo();\n"
"}\n"
"\n"
"Foo& f() {\n"
" return hello();\n"
"}");
ASSERT_EQUALS("[test.cpp:7]: (error) Reference to temporary returned.\n", errout.str());
// make sure function overloads are handled properly
check("class Foo;\n"
"Foo & hello(bool) {\n"
" static Foo foo;\n"
" return foo;\n"
"}\n"
"Foo hello() {\n"
" return Foo();\n"
"}\n"
"\n"
"Foo& f() {\n"
" return hello(true);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("Foo hello() {\n"
" return Foo();\n"
"}\n"
"\n"
"Foo& f() {\n" // Unknown type - might be a reference
" return hello();\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnReference2() {
check("class Fred {\n"
" std::string &foo();\n"
"}\n"
"std::string &Fred::foo()\n"
"{\n"
" std::string s;\n"
" return s;\n"
"}");
ASSERT_EQUALS("[test.cpp:7]: (error) Reference to local variable returned.\n", errout.str());
check("class Fred {\n"
" std::vector &foo();\n"
"};\n"
"std::vector &Fred::foo()\n"
"{\n"
" std::vector v;\n"
" return v;\n"
"}");
ASSERT_EQUALS("[test.cpp:7]: (error) Reference to local variable returned.\n", errout.str());
check("class Fred {\n"
" std::vector &foo();\n"
"};\n"
"std::vector &Fred::foo()\n"
"{\n"
" static std::vector v;\n"
" return v;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("class Fred {\n"
" std::string &f();\n"
"};\n"
"std::string hello()\n"
"{\n"
" return \"hello\";\n"
"}\n"
"std::string &Fred::f()\n"
"{\n"
" return hello();\n"
"}");
ASSERT_EQUALS("[test.cpp:10]: (error) Reference to temporary returned.\n", errout.str());
check("class Fred {\n"
" std::string hello();\n"
" std::string &f();\n"
"};\n"
"std::string Fred::hello()\n"
"{\n"
" return \"hello\";\n"
"}\n"
"std::string &Fred::f()\n"
"{\n"
" return hello();\n"
"}");
ASSERT_EQUALS("[test.cpp:11]: (error) Reference to temporary returned.\n", errout.str());
check("class Bar;\n"
"Bar foo() {\n"
" return something;\n"
"}\n"
"Bar& bar() {\n"
" return foo();\n"
"}");
ASSERT_EQUALS("[test.cpp:6]: (error) Reference to temporary returned.\n", errout.str());
check("std::map foo() {\n"
" return something;\n"
"}\n"
"std::map& bar() {\n"
" return foo();\n"
"}");
ASSERT_EQUALS("[test.cpp:5]: (error) Reference to temporary returned.\n", errout.str());
check("Bar foo() {\n"
" return something;\n"
"}\n"
"Bar& bar() {\n" // Unknown type - might be a typedef to a reference type
" return foo();\n"
"}");
ASSERT_EQUALS("", errout.str());
// Don't crash with function in unknown scope (#4076)
check("X& a::Bar() {}"
"X& foo() {"
" return Bar();"
"}");
}
void returnReference3() {
check("double & f(double & rd) {\n"
" double ret = getValue();\n"
" rd = ret;\n"
" return rd;\n"
"}", false);
ASSERT_EQUALS("", errout.str());
}
// Returning reference to global variable
void returnReference4() {
check("double a;\n"
"double & f() {\n"
" return a;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnReference5() {
check("struct A {\n"
" int i;\n"
"};\n"
"struct B {\n"
" A a;\n"
"};\n"
"struct C {\n"
" B *b;\n"
" const A& a() const {\n"
" const B *pb = b;\n"
" const A &ra = pb->a;\n"
" return ra;\n"
" }\n"
"};");
ASSERT_EQUALS("", errout.str());
}
void returnReference6() {
check("Fred & create() {\n"
" Fred &fred(*new Fred);\n"
" return fred;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnReference7() { // 3791 - false positive for overloaded function
check("std::string a();\n"
"std::string &a(int);\n"
"std::string &b() {\n"
" return a(12);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("std::string &a(int);\n"
"std::string a();\n"
"std::string &b() {\n"
" return a(12);\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnReferenceFunction() {
check("int& f(int& a) {\n"
" return a;\n"
"}\n"
"int& hello() {\n"
" int x = 0;\n"
" return f(x);\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:1] -> [test.cpp:2] -> [test.cpp:6] -> [test.cpp:6]: (error) Reference to local variable returned.\n",
errout.str());
check("int& f(int& a) {\n"
" return a;\n"
"}\n"
"int* hello() {\n"
" int x = 0;\n"
" return &f(x);\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:1] -> [test.cpp:2] -> [test.cpp:6] -> [test.cpp:6] -> [test.cpp:5] -> [test.cpp:6]: (error) Returning pointer to local variable 'x' that will be invalid when returning.\n",
errout.str());
check("int* f(int * x) {\n"
" return x;\n"
"}\n"
"int * g(int x) {\n"
" return f(&x);\n"
"}\n");
ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:5] -> [test.cpp:4] -> [test.cpp:5]: (error) Returning pointer to local variable 'x' that will be invalid when returning.\n", errout.str());
check("int* f(int * x) {\n"
" x = nullptr;\n"
" return x;\n"
"}\n"
"int * g(int x) {\n"
" return f(&x);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int f(int& a) {\n"
" return a;\n"
"}\n"
"int& hello() {\n"
" int x = 0;\n"
" return f(x);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int& f(int a) {\n"
" return a;\n"
"}\n"
"int& hello() {\n"
" int x = 0;\n"
" return f(x);\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2]: (error) Reference to local variable returned.\n", errout.str());
check("int f(int a) {\n"
" return a;\n"
"}\n"
"int& hello() {\n"
" int x = 0;\n"
" return f(x);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("template\n"
"int& f(int& x, T y) {\n"
" x += y;\n"
" return x;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void returnReferenceContainer() {
check("auto& f() {\n"
" std::vector x;\n"
" return x[0];\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (error) Reference to local variable returned.\n", errout.str());
check("struct A { int foo; };\n"
"int& f(std::vector v) {\n"
" auto it = v.begin();\n"
" return it->foo;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4]: (error) Reference to local variable returned.\n", errout.str());
check("template \n"
"const V& get_default(const T& t, const K& k, const V& v) {\n"
" auto it = t.find(k);\n"
" if (it == t.end()) return v;\n"
" return it->second;\n"
"}\n"
"const int& bar(const std::unordered_map& m, int k) {\n"
" auto x = 0;\n"
" return get_default(m, k, x);\n"
"}\n",
true);
ASSERT_EQUALS(
"[test.cpp:2] -> [test.cpp:4] -> [test.cpp:9] -> [test.cpp:9]: (error, inconclusive) Reference to local variable returned.\n",
errout.str());
check("struct A { int foo; };\n"
"int& f(std::vector& v) {\n"
" auto it = v.begin();\n"
" return it->foo;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void returnReferenceLiteral() {
check("const std::string &a() {\n"
" return \"foo\";\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (error) Reference to temporary returned.\n", errout.str());
check("const std::string a() {\n"
" return \"foo\";\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnReferenceCalculation() {
check("const std::string &a(const std::string& str) {\n"
" return \"foo\" + str;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (error) Reference to temporary returned.\n", errout.str());
check("int& operator<<(int out, int path) {\n"
" return out << path;\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (error) Reference to temporary returned.\n", errout.str());
check("std::ostream& operator<<(std::ostream& out, const std::string& path) {\n"
" return out << path;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("std::ostream& operator<<(std::ostream* out, const std::string& path) {\n"
" return *out << path;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("Unknown1& operator<<(Unknown1 out, Unknown2 path) {\n"
" return out << path;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("int& a(int b) {\n"
" return 2*(b+1);\n"
"}");
ASSERT_EQUALS("[test.cpp:2]: (error) Reference to temporary returned.\n", errout.str());
check("const std::string &a(const std::string& str) {\n"
" return str;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("const std::string &a(int bar) {\n"
" return foo(bar + 1);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("const std::string a(const std::string& str) {\n"
" return \"foo\" + str;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("int& incValue(int& value) {\n"
" return ++value;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnReferenceLambda() {
// #6787
check("const Item& foo(const Container& items) const {\n"
" return bar(items.begin(), items.end(),\n"
" [](const Item& lhs, const Item& rhs) {\n"
" return false;\n"
" });\n"
"}");
ASSERT_EQUALS("", errout.str());
// #5844
check("map const &getVariableTable() {\n"
"static map const s_var = []{\n"
" map var;\n"
" return var;\n"
" }();\n"
"return s_var;\n"
"}");
ASSERT_EQUALS("", errout.str());
// #7583
check("Command& foo() {\n"
" return f([]() -> int { return 1; });\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnReferenceInnerScope() {
// #6951
check("const Callback& make() {\n"
" struct _Wrapper {\n"
" static ulong call(void* o, const void* f, const void*[]) {\n"
" return 1;\n"
" }\n"
" };\n"
" return _make(_Wrapper::call, pmf);\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnReferenceRecursive() {
check("int& f() { return f(); }");
ASSERT_EQUALS("", errout.str());
check("int& g(int& i) { return i; }\n"
"int& f() { return g(f()); }\n");
ASSERT_EQUALS("", errout.str());
}
void danglingReference() {
check("int f( int k )\n"
"{\n"
" static int &r = k;\n"
" return r;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:3]: (error) Non-local reference variable 'r' to local variable 'k'\n",
errout.str());
check("int &f( int & k )\n"
"{\n"
" static int &r = k;\n"
" return r;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void testglobalnamespace() {
check("class SharedPtrHolder\n"
"{\n"
" ::std::tr1::shared_ptr pNum;\n"
"public:\n"
" void SetNum(const ::std::tr1::shared_ptr & apNum)\n"
" {\n"
" pNum = apNum;\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void returnParameterAddress() {
check("int* foo(int y)\n"
"{\n"
" return &y;\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:1] -> [test.cpp:3]: (error) Returning pointer to local variable 'y' that will be invalid when returning.\n", errout.str());
check("int ** foo(int * y)\n"
"{\n"
" return &y;\n"
"}");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:1] -> [test.cpp:3]: (error) Returning pointer to local variable 'y' that will be invalid when returning.\n", errout.str());
check("const int * foo(const int & y)\n"
"{\n"
" return &y;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("int * foo(int * y)\n"
"{\n"
" return y;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("struct s { void *p; };\n"
"extern struct s* f(void);\n"
"void g(void **q)\n"
"{\n"
" struct s *r = f();\n"
" *q = &r->p;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void testconstructor() { // Ticket #5478 - crash while checking a constructor
check("class const_tree_iterator {\n"
" const_tree_iterator(bool (*_incream)(node_type*&)) {}\n"
" const_tree_iterator& parent() {\n"
" return const_tree_iterator(foo);\n"
" }\n"
"};");
}
void variableIsUsedInScope() {
check("void removed_cb (GList *uids) {\n"
"for (; uids; uids = uids->next) {\n"
"}\n"
"}\n"
"void opened_cb () {\n"
" g_signal_connect (G_CALLBACK (removed_cb));\n"
"}");
}
void danglingLifetimeLambda() {
check("auto f() {\n"
" int a = 1;\n"
" auto l = [&](){ return a; };\n"
" return l;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning lambda that captures local variable 'a' that will be invalid when returning.\n", errout.str());
check("auto f() {\n"
" int a = 1;\n"
" return [&](){ return a; };\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning lambda that captures local variable 'a' that will be invalid when returning.\n", errout.str());
check("auto f(int a) {\n"
" return [&](){ return a; };\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:1] -> [test.cpp:2]: (error) Returning lambda that captures local variable 'a' that will be invalid when returning.\n", errout.str());
check("auto f(int a) {\n"
" auto p = &a;\n"
" return [=](){ return p; };\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3] -> [test.cpp:1] -> [test.cpp:3]: (error) Returning lambda that captures local variable 'a' that will be invalid when returning.\n", errout.str());
check("auto g(int& a) {\n"
" int p = a;\n"
" return [&](){ return p; };\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning lambda that captures local variable 'p' that will be invalid when returning.\n", errout.str());
check("auto f() {\n"
" return [=](){\n"
" int a = 1;\n"
" return [&](){ return a; };\n"
" };\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:3] -> [test.cpp:4]: (error) Returning lambda that captures local variable 'a' that will be invalid when returning.\n", errout.str());
check("auto f(int b) {\n"
" return [=](int a){\n"
" a += b;\n"
" return [&](){ return a; };\n"
" };\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning lambda that captures local variable 'a' that will be invalid when returning.\n", errout.str());
check("auto g(int& a) {\n"
" return [&](){ return a; };\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("auto g(int a) {\n"
" auto p = a;\n"
" return [=](){ return p; };\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("auto g(int& a) {\n"
" auto p = a;\n"
" return [=](){ return p; };\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("auto g(int& a) {\n"
" int& p = a;\n"
" return [&](){ return p; };\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("template\n"
"void g(F);\n"
"auto f() {\n"
" int x;\n"
" return g([&]() { return x; });\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void danglingLifetimeContainer() {
check("auto f(const std::vector& x) {\n"
" auto it = x.begin();\n"
" return it;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("auto f() {\n"
" std::vector x;\n"
" auto it = x.begin();\n"
" return it;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning iterator to local container 'x' that will be invalid when returning.\n", errout.str());
check("auto f() {\n"
" std::vector x;\n"
" auto p = x.data();\n"
" return p;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'x' that will be invalid when returning.\n", errout.str());
check("auto f() {\n"
" std::vector x;\n"
" auto p = &x[0];\n"
" return p;\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning pointer to local variable 'x' that will be invalid when returning.\n",
errout.str());
check("struct A { int foo; };\n"
"int* f(std::vector v) {\n"
" auto it = v.begin();\n"
" return &it->foo;\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:4] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'v' that will be invalid when returning.\n",
errout.str());
check("auto f(std::vector x) {\n"
" auto it = x.begin();\n"
" return it;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:1] -> [test.cpp:3]: (error) Returning iterator to local container 'x' that will be invalid when returning.\n", errout.str());
check("auto f() {\n"
" std::vector x;\n"
" auto it = x.begin();\n"
" return std::next(it);\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:4] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'x' that will be invalid when returning.\n",
errout.str());
check("auto f() {\n"
" std::vector x;\n"
" auto it = x.begin();\n"
" return it + 1;\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning iterator to local container 'x' that will be invalid when returning.\n",
errout.str());
check("auto f() {\n"
" std::vector x;\n"
" auto it = x.begin();\n"
" return std::next(it + 1);\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:4] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'x' that will be invalid when returning.\n",
errout.str());
check("std::vector f() {\n"
" int i = 0;\n"
" std::vector v;\n"
" v.push_back(&i);\n"
" return v;\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:4] -> [test.cpp:4] -> [test.cpp:2] -> [test.cpp:5]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
errout.str());
check("std::vector f() {\n"
" std::vector r;\n"
" int i = 0;\n"
" std::vector v;\n"
" v.push_back(&i);\n"
" r.assign(v.begin(), v.end());\n"
" return r;\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:5] -> [test.cpp:5] -> [test.cpp:5] -> [test.cpp:3] -> [test.cpp:7]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
errout.str());
check("struct A {\n"
" std::vector v;\n"
" void f() {\n"
" int i;\n"
" v.push_back(&i);\n"
" }\n"
"};\n");
ASSERT_EQUALS(
"[test.cpp:5] -> [test.cpp:5] -> [test.cpp:4] -> [test.cpp:5]: (error) Non-local variable 'v' will use object that points to local variable 'i'.\n",
errout.str());
check("struct A {\n"
" std::vector v;\n"
" void f() {\n"
" int i;\n"
" int * p = &i;\n"
" v.push_back(p);\n"
" }\n"
"};\n");
ASSERT_EQUALS(
"[test.cpp:5] -> [test.cpp:6] -> [test.cpp:4] -> [test.cpp:6]: (error) Non-local variable 'v' will use object that points to local variable 'i'.\n",
errout.str());
check("struct A {\n"
" std::vector m;\n"
" void f() {\n"
" int x;\n"
" std::vector v;\n"
" v.push_back(&x);\n"
" m.insert(m.end(), v.begin(), v.end());\n"
" }\n"
"};\n");
ASSERT_EQUALS(
"[test.cpp:6] -> [test.cpp:6] -> [test.cpp:6] -> [test.cpp:4] -> [test.cpp:7]: (error) Non-local variable 'm' will use object that points to local variable 'x'.\n",
errout.str());
check("std::vector::iterator f(std::vector v) {\n"
" for(auto it = v.begin();it != v.end();it++) {\n"
" return it;\n"
" }\n"
" return {};\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:2] -> [test.cpp:1] -> [test.cpp:3]: (error) Returning iterator to local container 'v' that will be invalid when returning.\n",
errout.str());
check("const char * f() {\n"
" std::string ba(\"hello\");\n"
" return ba.c_str();\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning pointer to local variable 'ba' that will be invalid when returning.\n",
errout.str());
check("template \n"
"const V* get_default(const T& t, const K& k, const V* v) {\n"
" auto it = t.find(k);\n"
" if (it == t.end()) return v;\n"
" return &it->second;\n"
"}\n"
"const int* bar(const std::unordered_map& m, int k) {\n"
" auto x = 0;\n"
" return get_default(m, k, &x);\n"
"}\n",
true);
ASSERT_EQUALS(
"[test.cpp:9] -> [test.cpp:9] -> [test.cpp:8] -> [test.cpp:9]: (error, inconclusive) Returning pointer to local variable 'x' that will be invalid when returning.\n",
errout.str());
check("struct A {\n"
" std::vector v;\n"
" void f() {\n"
" char s[3];\n"
" v.push_back(s);\n"
" }\n"
"};\n");
ASSERT_EQUALS("", errout.str());
check("std::vector f() {\n"
" const char * s = \"hello\";\n"
" std::vector v;\n"
" v.push_back(s);\n"
" return v;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("auto f() {\n"
" static std::vector x;\n"
" return x.begin();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("std::string g() {\n"
" std::vector v;\n"
" return v.data();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("std::vector::iterator f(std::vector* v) {\n"
" return v->begin();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("std::vector::iterator f(std::vector* v) {\n"
" std::vector* v = new std::vector();\n"
" return v->begin();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int f(std::vector v) {\n"
" return *v.begin();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int f(std::vector v) {\n"
" return v.end() - v.begin();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("auto g() {\n"
" std::vector v;\n"
" return {v, [v]() { return v.data(); }};\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("template\n"
"void g(F);\n"
"auto f() {\n"
" std::vector v;\n"
" return g([&]() { return v.data(); });\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("std::vector g();\n"
"struct A {\n"
" std::vector m;\n"
" void f() {\n"
" std::vector v = g();\n"
" m.insert(m.end(), v.begin(), v.end());\n"
" }\n"
"};\n");
ASSERT_EQUALS("", errout.str());
check("void f(bool b) {\n"
" std::vector v = {1};\n"
" if (b) {\n"
" int a[] = {0};\n"
" v.insert(a, a+1);\n"
" }\n"
" return v.back() == 0;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("class A {\n"
" int f( P p ) {\n"
" std::vector< S > maps;\n"
" m2.insert( m1.begin(), m1.end() );\n"
" }\n"
" struct B {};\n"
" std::map< S, B > m1;\n"
" std::map< S, B > m2;\n"
"};\n");
ASSERT_EQUALS("", errout.str());
check("struct A {\n"
" std::vector v;\n"
" int x;\n"
" void f() {\n"
" v.push_back(&x);\n"
" }\n"
"};\n");
ASSERT_EQUALS("", errout.str());
check("size_t f(const std::string& x) {\n"
" std::string y = \"x\";\n"
" return y.find(x);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("std::string* f();\n"
"const char* g() {\n"
" std::string* var = f();\n"
" return var->c_str();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void danglingLifetime() {
check("auto f() {\n"
" std::vector a;\n"
" auto it = a.begin();\n"
" return [=](){ return it; };\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:4] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning lambda that captures local variable 'a' that will be invalid when returning.\n", errout.str());
check("auto f(std::vector a) {\n"
" auto it = a.begin();\n"
" return [=](){ return it; };\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3] -> [test.cpp:1] -> [test.cpp:3]: (error) Returning lambda that captures local variable 'a' that will be invalid when returning.\n", errout.str());
check("struct e {};\n"
"e * j() {\n"
" e c[20];\n"
" return c;\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:4] -> [test.cpp:3] -> [test.cpp:4]: (error) Returning pointer to local variable 'c' that will be invalid when returning.\n",
errout.str());
check("auto f(std::vector& a) {\n"
" auto it = a.begin();\n"
" return [=](){ return it; };\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int * f(int a[]) {\n"
" return a;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" struct b {\n"
" uint32_t f[6];\n"
" } d;\n"
" uint32_t *a = d.f;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// Don't decay std::array
check("std::array f() {\n"
" std::array x;\n"
" return x;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// Make sure we don't hang
check("struct A;\n"
"void f() {\n"
" using T = A[3];\n"
" A &&a = T{1, 2, 3}[1];\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// Make sure we don't hang
check("struct A;\n"
"void f() {\n"
" using T = A[3];\n"
" A &&a = T{1, 2, 3}[1]();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// Make sure we don't hang
check("struct A;\n"
"void f() {\n"
" using T = A[3];\n"
" A &&a = T{1, 2, 3}[1];\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// Make sure we don't hang
check("struct A;\n"
"void f() {\n"
" using T = A[3];\n"
" A &&a = T{1, 2, 3}[1]();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// Crash #8872
check("struct a {\n"
" void operator()(b c) override {\n"
" d(c, [&] { c->e });\n"
" }\n"
"};\n");
ASSERT_EQUALS("", errout.str());
check("struct a {\n"
" void operator()(b c) override {\n"
" d(c, [=] { c->e });\n"
" }\n"
"};\n");
ASSERT_EQUALS("", errout.str());
check("struct a {\n"
" a(char* b) {}\n"
"};\n"
"a f() {\n"
" char c[20];\n"
" return c;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct a {\n"
" a(char* b) {}\n"
"};\n"
"a g() {\n"
" char c[20];\n"
" a d = c;\n"
" return d;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" struct a {\n"
" std::vector v;\n"
" auto g() { return v.end(); }\n"
" };\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int * f(std::vector& v) {\n"
" for(int & x : v)\n"
" return &x;\n"
" return nullptr;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// #9275
check("struct S {\n"
" void f();\n"
" std::string m;\n"
"}\n"
"void S::f() {\n"
" char buf[1024];\n"
" const char* msg = buf;\n"
" m = msg;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void danglingLifetimeFunction() {
check("auto f() {\n"
" int a;\n"
" return std::ref(a);\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning object that points to local variable 'a' that will be invalid when returning.\n",
errout.str());
check("auto f() {\n"
" int a;\n"
" return std::make_tuple(std::ref(a));\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning object that points to local variable 'a' that will be invalid when returning.\n",
errout.str());
check("template\n"
"auto by_value(T x) {\n"
" return [=] { return x; };\n"
"}\n"
"auto g() {\n"
" std::vector v;\n"
" return by_value(v.begin());\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:7] -> [test.cpp:7] -> [test.cpp:3] -> [test.cpp:3] -> [test.cpp:6] -> [test.cpp:7]: (error) Returning object that points to local variable 'v' that will be invalid when returning.\n",
errout.str());
check("auto by_ref(int& x) {\n"
" return [&] { return x; };\n"
"}\n"
"auto f() {\n"
" int i = 0;\n"
" return by_ref(i);\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:2] -> [test.cpp:1] -> [test.cpp:2] -> [test.cpp:6] -> [test.cpp:5] -> [test.cpp:6]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
errout.str());
check("auto f(int x) {\n"
" int a;\n"
" std::tie(a) = x;\n"
" return a;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void danglingLifetimeAggegrateConstructor() {
check("struct A {\n"
" const int& x;\n"
" int y;\n"
"};\n"
"A f() {\n"
" int i = 0;\n"
" return A{i, i};\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:7] -> [test.cpp:6] -> [test.cpp:7]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
errout.str());
check("struct A {\n"
" const int& x;\n"
" int y;\n"
"};\n"
"A f() {\n"
" int i = 0;\n"
" return {i, i};\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:7] -> [test.cpp:6] -> [test.cpp:7]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
errout.str());
// TODO: Ast is missing for this case
check("struct A {\n"
" const int& x;\n"
" int y;\n"
"};\n"
"A f() {\n"
" int i = 0;\n"
" A r{i, i};\n"
" return r;\n"
"}\n");
TODO_ASSERT_EQUALS(
"[test.cpp:7] -> [test.cpp:6] -> [test.cpp:7]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
"",
errout.str());
check("struct A {\n"
" const int& x;\n"
" int y;\n"
"};\n"
"A f() {\n"
" int i = 0;\n"
" A r = {i, i};\n"
" return r;\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:7] -> [test.cpp:6] -> [test.cpp:8]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
errout.str());
check("struct A {\n"
" const int& x;\n"
" int y;\n"
"};\n"
"A f(int& x) {\n"
" int i = 0;\n"
" return A{i, x};\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:7] -> [test.cpp:6] -> [test.cpp:7]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
errout.str());
check("struct A {\n"
" const int& x;\n"
" int y;\n"
"};\n"
"A f(int& x) {\n"
" int i = 0;\n"
" return A{x, i};\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct A {\n"
" const int& x;\n"
" int y;\n"
"};\n"
"A f(int& x) {\n"
" return A{x, x};\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct A { int i; const int& j; };\n"
"A f(int& x) {\n"
" int y = 0;\n"
" return A{y, x};\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void danglingLifetimeInitList() {
check("std::vector f() {\n"
" int i = 0;\n"
" std::vector v = {&i, &i};\n"
" return v;\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
errout.str());
// TODO: Ast is missing for this case
check("std::vector f() {\n"
" int i = 0;\n"
" std::vector v{&i, &i};\n"
" return v;\n"
"}\n");
TODO_ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:4]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
"",
errout.str());
check("std::vector f() {\n"
" int i = 0;\n"
" return {&i, &i};\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:3] -> [test.cpp:3] -> [test.cpp:2] -> [test.cpp:3]: (error) Returning object that points to local variable 'i' that will be invalid when returning.\n",
errout.str());
check("std::vector f(int& x) {\n"
" return {&x, &x};\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void danglingLifetimeImplicitConversion() {
check("struct A { A(const char *a); };\n"
"A f() {\n"
" std::string ba(\"hello\");\n"
" return ba.c_str();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct A { A(const char *a); };\n"
"A f() {\n"
" std::string ba(\"hello\");\n"
" A bp = ba.c_str();\n"
" return bp;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct A { A(const char *a); };\n"
"std::vector f() {\n"
" std::string ba(\"hello\");\n"
" std::vector v;\n"
" v.push_back(ba.c_str());\n"
" return v;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("std::string f(const std::string& x) {\n"
" const char c[] = \"\";\n"
" if (!x.empty())\n"
" return x + c;\n"
" return \"\";\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("std::string f(const std::string& x) {\n"
" const char c[] = \"123\";\n"
" if (!x.empty())\n"
" return c + 1;\n"
" return \"\";\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void invalidLifetime() {
check("void foo(int a) {\n"
" std::function f;\n"
" if (a > 0) {\n"
" int b = a + 1;\n"
" f = [&]{ return b; };\n"
" }\n"
" f();\n"
"}\n");
ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:4] -> [test.cpp:7]: (error) Using lambda that captures local variable 'b' that is out of scope.\n", errout.str());
check("void f(bool b) {\n"
" int* x;\n"
" if(b) {\n"
" int y[6] = {0,1,2,3,4,5};\n"
" x = y;\n"
" }\n"
" x[3];\n"
"}\n");
ASSERT_EQUALS(
"[test.cpp:5] -> [test.cpp:4] -> [test.cpp:7]: (error) Using pointer to local variable 'y' that is out of scope.\n",
errout.str());
check("void foo(int a) {\n"
" std::function f;\n"
" if (a > 0) {\n"
" int b = a + 1;\n"
" f = [&]{ return b; };\n"
" f();\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct a {\n"
" b();\n"
" std::list c;\n"
"};\n"
"void a::b() {\n"
" c.end()\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void b(char f[], char c[]) {\n"
" std::string d(c); {\n"
" std::string e;\n"
" b(f, e.c_str())\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(bool b) {\n"
" std::string s;\n"
" if(b) {\n"
" char buf[3];\n"
" s = buf;\n"
" }\n"
" std::cout << s;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("int &a[];\n"
"void b(){int *c = a};\n");
ASSERT_EQUALS("", errout.str());
}
void deadPointer() {
check("void f() {\n"
" int *p = p1;\n"
" if (cond) {\n"
" int x;\n"
" p = &x;\n"
" }\n"
" *p = 0;\n"
"}");
ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:4] -> [test.cpp:7]: (error) Using pointer to local variable 'x' that is out of scope.\n", errout.str());
// FP: don't warn in subfunction
check("void f(struct KEY *key) {\n"
" key->x = 0;\n"
"}\n"
"\n"
"int main() {\n"
" struct KEY *tmp = 0;\n"
" struct KEY k;\n"
"\n"
" if (condition) {\n"
" tmp = &k;\n"
" } else {\n"
" }\n"
" f(tmp);\n"
"}");
ASSERT_EQUALS("", errout.str());
// Don't warn about references (#6399)
check("void f() {\n"
" wxAuiToolBarItem* former_hover = NULL;\n"
" for (i = 0, count = m_items.GetCount(); i < count; ++i) {\n"
" wxAuiToolBarItem& item = m_items.Item(i);\n"
" former_hover = &item;\n"
" }\n"
" if (former_hover != pitem)\n"
" dosth();\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" wxAuiToolBarItem* former_hover = NULL;\n"
" for (i = 0, count = m_items.GetCount(); i < count; ++i) {\n"
" wxAuiToolBarItem item = m_items.Item(i);\n"
" former_hover = &item;\n"
" }\n"
" if (former_hover != pitem)\n"
" dosth();\n"
"}");
ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:4] -> [test.cpp:7]: (error) Using pointer to local variable 'item' that is out of scope.\n", errout.str());
// #6575
check("void trp_deliver_signal() {\n"
" union {\n"
" Uint32 theData[25];\n"
" EventReport repData;\n"
" };\n"
" EventReport * rep = &repData;\n"
" rep->setEventType(NDB_LE_Connected);\n"
"}");
ASSERT_EQUALS("", errout.str());
// #8785
check("int f(bool a, bool b) {\n"
" int *iPtr = 0;\n"
" if(b) {\n"
" int x = 42;\n"
" iPtr = &x;\n"
" }\n"
" if(b && a)\n"
" return *iPtr;\n"
" return 0;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:4] -> [test.cpp:8]: (error) Using pointer to local variable 'x' that is out of scope.\n", errout.str());
}
};
REGISTER_TEST(TestAutoVariables)