/* * Cppcheck - A tool for static C/C++ code analysis * Copyright (C) 2007-2022 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 "checkstring.h" #include "errortypes.h" #include "settings.h" #include "testsuite.h" #include "tokenize.h" #include <sstream> // IWYU pragma: keep class TestString : public TestFixture { public: TestString() : TestFixture("TestString") {} private: Settings settings; void run() override { settings.severity.enable(Severity::warning); settings.severity.enable(Severity::style); TEST_CASE(stringLiteralWrite); TEST_CASE(alwaysTrueFalseStringCompare); TEST_CASE(suspiciousStringCompare); TEST_CASE(suspiciousStringCompare_char); TEST_CASE(strPlusChar1); // "/usr" + '/' TEST_CASE(strPlusChar2); // "/usr" + ch TEST_CASE(strPlusChar3); // ok: path + "/sub" + '/' TEST_CASE(strPlusChar4); // L"/usr" + L'/' TEST_CASE(snprintf1); // Dangerous usage of snprintf TEST_CASE(sprintf1); // Dangerous usage of sprintf TEST_CASE(sprintf2); TEST_CASE(sprintf3); TEST_CASE(sprintf4); // struct member TEST_CASE(sprintf5); // another struct member TEST_CASE(sprintf6); // (char*) TEST_CASE(sprintf7); // (char*)(void*) TEST_CASE(wsprintf1); // Dangerous usage of wsprintf TEST_CASE(incorrectStringCompare); TEST_CASE(deadStrcmp); } #define check(...) check_(__FILE__, __LINE__, __VA_ARGS__) void check_(const char* file, int line, const char code[], const char filename[] = "test.cpp") { // Clear the error buffer.. errout.str(""); // Tokenize.. Tokenizer tokenizer(&settings, this); std::istringstream istr(code); ASSERT_LOC(tokenizer.tokenize(istr, filename), file, line); // Check char variable usage.. CheckString checkString(&tokenizer, &settings, this); checkString.runChecks(&tokenizer, &settings, this); } void stringLiteralWrite() { check("void f() {\n" " char *abc = \"abc\";\n" " abc[0] = 'a';\n" "}"); ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2]: (error) Modifying string literal \"abc\" directly or indirectly is undefined behaviour.\n", errout.str()); check("void f() {\n" " char *abc = \"abc\";\n" " *abc = 'a';\n" "}"); ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2]: (error) Modifying string literal \"abc\" directly or indirectly is undefined behaviour.\n", errout.str()); check("void f() {\n" " char *abc = \"A very long string literal\";\n" " abc[0] = 'a';\n" "}"); ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2]: (error) Modifying string literal \"A very long stri..\" directly or indirectly is undefined behaviour.\n", errout.str()); check("void f() {\n" " QString abc = \"abc\";\n" " abc[0] = 'a';\n" "}"); ASSERT_EQUALS("", errout.str()); check("void foo_FP1(char *p) {\n" " p[1] = 'B';\n" "}\n" "void foo_FP2(void) {\n" " char* s = \"Y\";\n" " foo_FP1(s);\n" "}"); ASSERT_EQUALS( "[test.cpp:2] -> [test.cpp:5]: (error) Modifying string literal \"Y\" directly or indirectly is undefined behaviour.\n", errout.str()); check("void foo_FP1(char *p) {\n" " p[1] = 'B';\n" "}\n" "void foo_FP2(void) {\n" " char s[10] = \"Y\";\n" " foo_FP1(s);\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f() {\n" " wchar_t *abc = L\"abc\";\n" " abc[0] = u'a';\n" "}"); ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2]: (error) Modifying string literal L\"abc\" directly or indirectly is undefined behaviour.\n", errout.str()); check("void f() {\n" " char16_t *abc = u\"abc\";\n" " abc[0] = 'a';\n" "}"); ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:2]: (error) Modifying string literal u\"abc\" directly or indirectly is undefined behaviour.\n", errout.str()); check("void foo() {\n" // #8332 " int i;\n" " char *p = \"string literal\";\n" " for( i = 0; i < strlen(p); i++) {\n" " p[i] = \'X\';\n" // << " }\n" " printf(\"%s\\n\", p);\n" "}"); ASSERT_EQUALS("[test.cpp:5] -> [test.cpp:3]: (error) Modifying string literal \"string literal\" directly or indirectly is undefined behaviour.\n", errout.str()); } void alwaysTrueFalseStringCompare() { check("void f() {\n" " if (strcmp(\"A\",\"A\")){}\n" " if (strncmp(\"A\",\"A\",1)){}\n" " if (strcasecmp(\"A\",\"A\")){}\n" " if (strncasecmp(\"A\",\"A\",1)){}\n" " if (memcmp(\"A\",\"A\",1)){}\n" " if (strverscmp(\"A\",\"A\")){}\n" " if (bcmp(\"A\",\"A\",1)){}\n" " if (wcsncasecmp(L\"A\",L\"A\",1)){}\n" " if (wcsncmp(L\"A\",L\"A\",1)){}\n" " if (wmemcmp(L\"A\",L\"A\",1)){}\n" " if (wcscmp(L\"A\",L\"A\")){}\n" " if (wcscasecmp(L\"A\",L\"A\")){}\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:3]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:4]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:5]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:6]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:7]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:8]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:9]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:10]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:11]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:12]: (warning) Unnecessary comparison of static strings.\n" "[test.cpp:13]: (warning) Unnecessary comparison of static strings.\n", errout.str()); // avoid false positives when the address is modified #6415 check("void f(void *p, int offset) {\n" " if (!memcmp(p, p + offset, 42)){}\n" " if (!memcmp(p + offset, p, 42)){}\n" " if (!memcmp(offset + p, p, 42)){}\n" " if (!memcmp(p, offset + p, 42)){}\n" "}"); ASSERT_EQUALS("", errout.str()); // avoid false positives when the address is modified #6415 check("void f(char *c, int offset) {\n" " if (!memcmp(c, c + offset, 42)){}\n" " if (!memcmp(c + offset, c, 42)){}\n" " if (!memcmp(offset + c, c, 42)){}\n" " if (!memcmp(c, offset + c, 42)){}\n" "}"); ASSERT_EQUALS("", errout.str()); // avoid false positives when the address is modified #6415 check("void f(std::string s, int offset) {\n" " if (!memcmp(s.c_str(), s.c_str() + offset, 42)){}\n" " if (!memcmp(s.c_str() + offset, s.c_str(), 42)){}\n" " if (!memcmp(offset + s.c_str(), s.c_str(), 42)){}\n" " if (!memcmp(s.c_str(), offset + s.c_str(), 42)){}\n" "}"); ASSERT_EQUALS("", errout.str()); check("int main()\n" "{\n" " if (strcmp(\"00FF00\", \"00FF00\") == 0)" " {" " std::cout << \"Equal\";" " }" "}"); ASSERT_EQUALS("[test.cpp:3]: (warning) Unnecessary comparison of static strings.\n", errout.str()); check("void f() {\n" " if (strcmp($\"00FF00\", \"00FF00\") == 0) {}" "}"); ASSERT_EQUALS("", errout.str()); check("void f() {\n" " if ($strcmp(\"00FF00\", \"00FF00\") == 0) {}" "}"); ASSERT_EQUALS("", errout.str()); check("int main()\n" "{\n" " if (stricmp(\"hotdog\",\"HOTdog\") == 0)" " {" " std::cout << \"Equal\";" " }" "}"); ASSERT_EQUALS("[test.cpp:3]: (warning) Unnecessary comparison of static strings.\n", errout.str()); check("int main()\n" "{\n" " if (QString::compare(\"Hamburger\", \"Hotdog\") == 0)" " {" " std::cout << \"Equal\";" " }" "}"); ASSERT_EQUALS("[test.cpp:3]: (warning) Unnecessary comparison of static strings.\n", errout.str()); check("int main()\n" "{\n" " if (QString::compare(argv[2], \"hotdog\") == 0)" " {" " std::cout << \"Equal\";" " }" "}"); ASSERT_EQUALS("", errout.str()); check("int main()\n" "{\n" " if (strncmp(\"hotdog\",\"hotdog\", 6) == 0)" " {" " std::cout << \"Equal\";" " }" "}"); ASSERT_EQUALS("[test.cpp:3]: (warning) Unnecessary comparison of static strings.\n", errout.str()); check("int foo(const char *buf)\n" "{\n" " if (strcmp(buf, buf) == 0)" " {" " std::cout << \"Equal\";" " }" "}"); ASSERT_EQUALS("[test.cpp:3]: (warning) Comparison of identical string variables.\n", errout.str()); check("int foo(const std::string& buf)\n" "{\n" " if (stricmp(buf.c_str(), buf.c_str()) == 0)" " {" " std::cout << \"Equal\";" " }" "}"); ASSERT_EQUALS("[test.cpp:3]: (warning) Comparison of identical string variables.\n", errout.str()); check("int main() {\n" " if (\"str\" == \"str\") {\n" " std::cout << \"Equal\";\n" " }\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Unnecessary comparison of static strings.\n", errout.str()); check("int main() {\n" " if (\"str\" != \"str\") {\n" " std::cout << \"Equal\";\n" " }\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Unnecessary comparison of static strings.\n", errout.str()); check("int main() {\n" " if (a+\"str\" != \"str\"+b) {\n" " std::cout << \"Equal\";\n" " }\n" "}"); ASSERT_EQUALS("", errout.str()); } void suspiciousStringCompare() { check("bool foo(char* c) {\n" " return c == \"x\";\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) String literal compared with variable 'c'. Did you intend to use strcmp() instead?\n", errout.str()); check("bool foo(char** c) {\n" " return c[3] == \"x\";\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) String literal compared with variable 'c[3]'. Did you intend to use strcmp() instead?\n", errout.str()); check("bool foo(wchar_t* c) {\n" " return c == L\"x\";\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) String literal compared with variable 'c'. Did you intend to use wcscmp() instead?\n", errout.str()); check("bool foo(const char* c) {\n" " return \"x\" == c;\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) String literal compared with variable 'c'. Did you intend to use strcmp() instead?\n", errout.str()); check("bool foo(char* c) {\n" " return foo+\"x\" == c;\n" "}"); ASSERT_EQUALS("", errout.str()); check("bool foo(char* c) {\n" " return \"x\" == c+foo;\n" "}", "test.cpp"); ASSERT_EQUALS("", errout.str()); check("bool foo(char* c) {\n" " return \"x\" == c+foo;\n" "}", "test.c"); ASSERT_EQUALS("[test.c:2]: (warning) String literal compared with variable 'c+foo'. Did you intend to use strcmp() instead?\n", errout.str()); check("bool foo(Foo c) {\n" " return \"x\" == c.foo;\n" "}", "test.cpp"); ASSERT_EQUALS("", errout.str()); check("bool foo(Foo c) {\n" " return \"x\" == c.foo;\n" "}", "test.c"); ASSERT_EQUALS("[test.c:2]: (warning) String literal compared with variable 'c.foo'. Did you intend to use strcmp() instead?\n", errout.str()); check("bool foo(const std::string& c) {\n" " return \"x\" == c;\n" "}"); ASSERT_EQUALS("", errout.str()); check("bool foo(const Foo* c) {\n" " return \"x\" == c->bar();\n" // #4314 "}"); ASSERT_EQUALS("", errout.str()); // Ticket #4257 check("bool foo() {\n" "MyString *str=Getter();\n" "return *str==\"bug\"; }\n", "test.c"); ASSERT_EQUALS("[test.c:3]: (warning) String literal compared with variable '*str'. Did you intend to use strcmp() instead?\n", errout.str()); // Ticket #4257 check("bool foo() {\n" "MyString *str=Getter();\n" "return *str==\"bug\"; }"); ASSERT_EQUALS("", errout.str()); // Ticket #4257 check("bool foo() {\n" "MyString **str=OtherGetter();\n" "return *str==\"bug\"; }", "test.c"); ASSERT_EQUALS("[test.c:3]: (warning) String literal compared with variable '*str'. Did you intend to use strcmp() instead?\n", errout.str()); // Ticket #4257 check("bool foo() {\n" "MyString str=OtherGetter2();\n" "return &str==\"bug\"; }", "test.c"); ASSERT_EQUALS("[test.c:3]: (warning) String literal compared with variable '&str'. Did you intend to use strcmp() instead?\n", errout.str()); // Ticket #5734 check("int foo(char c) {\n" "return c == '4';}", "test.cpp"); ASSERT_EQUALS("", errout.str()); check("int foo(char c) {\n" "return c == '4';}", "test.c"); ASSERT_EQUALS("", errout.str()); check("int foo(char c) {\n" "return c == \"42\"[0];}", "test.cpp"); ASSERT_EQUALS("", errout.str()); check("int foo(char c) {\n" "return c == \"42\"[0];}", "test.c"); ASSERT_EQUALS("", errout.str()); // 5639 String literal compared with char buffer in a struct check("struct Example {\n" " char buffer[200];\n" "};\n" "void foo() {\n" " struct Example example;\n" " if (example.buffer == \"test\") ;\n" "}\n", "test.cpp"); ASSERT_EQUALS("[test.cpp:6]: (warning) String literal compared with variable 'example.buffer'. Did you intend to use strcmp() instead?\n", errout.str()); check("struct Example {\n" " char buffer[200];\n" "};\n" "void foo() {\n" " struct Example example;\n" " if (example.buffer == \"test\") ;\n" "}\n", "test.c"); ASSERT_EQUALS("[test.c:6]: (warning) String literal compared with variable 'example.buffer'. Did you intend to use strcmp() instead?\n", errout.str()); // #9726 check("void f(std::vector<std::string> theArgs) {\n" " std::string arg1(*theArgs.begin());\n" " if(arg1 == \"aaa\") {}\n" "}"); ASSERT_EQUALS("", errout.str()); } void suspiciousStringCompare_char() { check("bool foo(char* c) {\n" " return c == 'x';\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Char literal compared with pointer 'c'. Did you intend to dereference it?\n", errout.str()); check("bool foo(wchar_t* c) {\n" " return c == L'x';\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Char literal compared with pointer 'c'. Did you intend to dereference it?\n", errout.str()); check("bool foo(char* c) {\n" " return '\\0' != c;\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Char literal compared with pointer 'c'. Did you intend to dereference it?\n", errout.str()); check("bool foo(char c) {\n" " return c == '\\0';\n" "}"); ASSERT_EQUALS("", errout.str()); check("bool foo(char* c) {\n" " return c[0] == '\\0';\n" "}"); ASSERT_EQUALS("", errout.str()); check("bool foo(char** c) {\n" " return c[0] == '\\0';\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Char literal compared with pointer 'c[0]'. Did you intend to dereference it?\n", errout.str()); check("bool foo(char** c) {\n" " return *c == '\\0';\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Char literal compared with pointer '*c'. Did you intend to dereference it?\n", errout.str()); check("bool foo(char c) {\n" " return c == 0;\n" "}"); ASSERT_EQUALS("", errout.str()); check("bool foo(char* c) {\n" " return *c == 0;\n" "}", "test.c"); ASSERT_EQUALS("", errout.str()); check("bool foo(char* c) {\n" " return *c == 0;\n" "}"); ASSERT_EQUALS("", errout.str()); check("bool foo(Foo* c) {\n" " return 0 == c->x;\n" "}"); ASSERT_EQUALS("", errout.str()); check("void foo(char* c) {\n" " if(c == '\\0') bar();\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Char literal compared with pointer 'c'. Did you intend to dereference it?\n", errout.str()); check("void f() {\n" " struct { struct { char *str; } x; } a;\n" " return a.x.str == '\\0';" "}"); ASSERT_EQUALS("[test.cpp:3]: (warning) Char literal compared with pointer 'a.x.str'. Did you intend to dereference it?\n", errout.str()); check("void f() {\n" " struct { struct { char *str; } x; } a;\n" " return *a.x.str == '\\0';" "}"); ASSERT_EQUALS("", errout.str()); } void snprintf1() { check("void foo()\n" "{\n" " char buf[100];\n" " snprintf(buf,100,\"%s\",buf);\n" "}"); ASSERT_EQUALS("[test.cpp:4]: (error) Undefined behavior: Variable 'buf' is used as parameter and destination in snprintf().\n", errout.str()); } void sprintf1() { check("void foo()\n" "{\n" " char buf[100];\n" " sprintf(buf,\"%s\",buf);\n" "}"); ASSERT_EQUALS("[test.cpp:4]: (error) Undefined behavior: Variable 'buf' is used as parameter and destination in sprintf().\n", errout.str()); } void sprintf2() { check("void foo()\n" "{\n" " char buf[100];\n" " sprintf(buf,\"%i\",sizeof(buf));\n" "}"); ASSERT_EQUALS("", errout.str()); } void sprintf3() { check("void foo()\n" "{\n" " char buf[100];\n" " sprintf(buf,\"%i\",sizeof(buf));\n" " if (buf[0]);\n" "}"); ASSERT_EQUALS("", errout.str()); } void sprintf4() { check("struct A\n" "{\n" " char filename[128];\n" "};\n" "\n" "void foo()\n" "{\n" " const char* filename = \"hello\";\n" " struct A a;\n" " snprintf(a.filename, 128, \"%s\", filename);\n" "}"); ASSERT_EQUALS("", errout.str()); } void sprintf5() { check("struct A\n" "{\n" " char filename[128];\n" "};\n" "\n" "void foo(struct A *a)\n" "{\n" " snprintf(a->filename, 128, \"%s\", a->filename);\n" "}"); ASSERT_EQUALS("[test.cpp:8]: (error) Undefined behavior: Variable 'a->filename' is used as parameter and destination in snprintf().\n", errout.str()); } void sprintf6() { check("void foo()\n" "{\n" " char buf[100];\n" " sprintf((char*)buf,\"%s\",(char*)buf);\n" "}"); ASSERT_EQUALS("[test.cpp:4]: (error) Undefined behavior: Variable 'buf' is used as parameter and destination in sprintf().\n", errout.str()); } void sprintf7() { check("void foo()\n" "{\n" " char buf[100];\n" " sprintf((char*)(void*)buf,\"%s\",(void*)(char*)buf);\n" "}"); ASSERT_EQUALS("[test.cpp:4]: (error) Undefined behavior: Variable 'buf' is used as parameter and destination in sprintf().\n", errout.str()); } void wsprintf1() { check("void foo()\n" "{\n" " wchar_t buf[100];\n" " swprintf(buf,10, \"%s\",buf);\n" "}"); ASSERT_EQUALS("[test.cpp:4]: (error) Undefined behavior: Variable 'buf' is used as parameter and destination in swprintf().\n", errout.str()); } void strPlusChar1() { // Strange looking pointer arithmetic.. check("void foo()\n" "{\n" " const char *p = \"/usr\" + '/';\n" "}"); ASSERT_EQUALS("[test.cpp:3]: (error) Unusual pointer arithmetic. A value of type 'char' is added to a string literal.\n", errout.str()); } void strPlusChar2() { // Strange looking pointer arithmetic.. check("void foo()\n" "{\n" " char ch = 1;\n" " const char *p = ch + \"/usr\";\n" "}"); ASSERT_EQUALS("", errout.str()); // Strange looking pointer arithmetic.. check("void foo()\n" "{\n" " int i = 1;\n" " const char* psz = \"Bla\";\n" " const std::string str = i + psz;\n" "}"); ASSERT_EQUALS("", errout.str()); } void strPlusChar3() { // Strange looking pointer arithmetic.. check("void foo()\n" "{\n" " std::string temp = \"/tmp\";\n" " std::string path = temp + '/' + \"sub\" + '/';\n" "}"); ASSERT_EQUALS("", errout.str()); } void strPlusChar4() { // Strange looking pointer arithmetic, wide char.. check("void foo()\n" "{\n" " const wchar_t *p = L\"/usr\" + L'/';\n" "}"); ASSERT_EQUALS("[test.cpp:3]: (error) Unusual pointer arithmetic. A value of type 'wchar_t' is added to a string literal.\n", errout.str()); check("void foo(wchar_t c)\n" "{\n" " const wchar_t *p = L\"/usr\" + c;\n" "}"); ASSERT_EQUALS("[test.cpp:3]: (error) Unusual pointer arithmetic. A value of type 'wchar_t' is added to a string literal.\n", errout.str()); } void incorrectStringCompare() { check("int f() {\n" " return test.substr( 0 , 4 ) == \"Hello\" ? 0 : 1 ;\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) String literal \"Hello\" doesn't match length argument for substr().\n", errout.str()); check("int f() {\n" " return test.substr( 0 , 4 ) == L\"Hello\" ? 0 : 1 ;\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) String literal L\"Hello\" doesn't match length argument for substr().\n", errout.str()); check("int f() {\n" " return test.substr( 0 , 5 ) == \"Hello\" ? 0 : 1 ;\n" "}"); ASSERT_EQUALS("", errout.str()); check("int f() {\n" " return \"Hello\" == test.substr( 0 , 4 ) ? 0 : 1 ;\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) String literal \"Hello\" doesn't match length argument for substr().\n", errout.str()); check("int f() {\n" " return \"Hello\" == foo.bar<int>().z[1].substr(i+j*4, 4) ? 0 : 1 ;\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) String literal \"Hello\" doesn't match length argument for substr().\n", errout.str()); check("int f() {\n" " return \"Hello\" == test.substr( 0 , 5 ) ? 0 : 1 ;\n" "}"); ASSERT_EQUALS("", errout.str()); check("int f() {\n" " if (\"Hello\") { }\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Conversion of string literal \"Hello\" to bool always evaluates to true.\n", errout.str()); check("int f() {\n" " if (\"Hello\" && test) { }\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Conversion of string literal \"Hello\" to bool always evaluates to true.\n", errout.str()); check("int f() {\n" " if (test && \"Hello\") { }\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Conversion of string literal \"Hello\" to bool always evaluates to true.\n", errout.str()); check("int f() {\n" " while (\"Hello\") { }\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Conversion of string literal \"Hello\" to bool always evaluates to true.\n", errout.str()); check("int f() {\n" " return \"Hello\" ? 1 : 2;\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Conversion of string literal \"Hello\" to bool always evaluates to true.\n", errout.str()); check("int f() {\n" " assert (test || \"Hello\");\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Conversion of string literal \"Hello\" to bool always evaluates to true.\n", errout.str()); check("int f() {\n" " assert (test && \"Hello\");\n" "}"); ASSERT_EQUALS("", errout.str()); check("int f() {\n" " assert (\"Hello\" || test);\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Conversion of string literal \"Hello\" to bool always evaluates to true.\n", errout.str()); check("int f() {\n" " assert (\"Hello\" && test);\n" "}"); ASSERT_EQUALS("", errout.str()); check("int f() {\n" " BOOST_ASSERT (\"Hello\" && test);\n" "}"); ASSERT_EQUALS("", errout.str()); check("int f() {\n" " return f2(\"Hello\");\n" "}"); ASSERT_EQUALS("", errout.str()); // #7750 warn about 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("[test.cpp:2]: (warning) Conversion of char literal 'a' to bool always evaluates to true.\n" "[test.cpp:3]: (warning) Conversion of char literal L'b' to bool always evaluates to true.\n" "[test.cpp:4]: (warning) Conversion of char literal 'c' to bool always evaluates to true.\n" "[test.cpp:5]: (warning) Conversion of char literal 'd' to bool always evaluates to true.\n" , errout.str()); check("void f() {\n" " if('\\0'){}\n" " if(L'\\0'){}\n" "}"); ASSERT_EQUALS("", errout.str()); check("void f() {\n" " if('\\0' || cond){}\n" " if(L'\\0' || cond){}\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) Conversion of char literal '\\0' to bool always evaluates to false.\n" "[test.cpp:3]: (warning) Conversion of char literal L'\\0' to bool always evaluates to false.\n", errout.str()); } void deadStrcmp() { check("void f(const char *str) {\n" " if (strcmp(str, \"abc\") == 0 || strcmp(str, \"def\")) {}\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) The expression 'strcmp(str,\"def\") != 0' is suspicious. It overlaps 'strcmp(str,\"abc\") == 0'.\n", errout.str()); check("void f(const wchar_t *str) {\n" " if (wcscmp(str, L\"abc\") == 0 || wcscmp(str, L\"def\")) {}\n" "}"); ASSERT_EQUALS("[test.cpp:2]: (warning) The expression 'wcscmp(str,L\"def\") != 0' is suspicious. It overlaps 'wcscmp(str,L\"abc\") == 0'.\n", errout.str()); check("struct X {\n" " char *str;\n" "};\n" "\n" "void f(const struct X *x) {\n" " if (strcmp(x->str, \"abc\") == 0 || strcmp(x->str, \"def\")) {}\n" "}"); ASSERT_EQUALS("[test.cpp:6]: (warning) The expression 'strcmp(x->str,\"def\") != 0' is suspicious. It overlaps 'strcmp(x->str,\"abc\") == 0'.\n", errout.str()); } }; REGISTER_TEST(TestString)