walkero
/
cppcheck
1
0
Fork 0
Code Issues Pull Requests Projects Releases 1 Wiki Activity

Fix 11306: FP knownConditionTrueFalse with strlen() (#4477) 

* Fix 11306: FP knownConditionTrueFalse with strlen()

* Add another test
This commit is contained in:
Paul Fultz II 2022-09-18 01:29:10 -05:00 committed by GitHub
parent 8126d5c1a6
commit d34de745c0
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 19 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
lib/valueflow.cpp
View File

@ -5223,16 +5223,11 @@ static void valueFlowSymbolicOperators(TokenList* tokenlist, SymbolDatabase* sym
continue; continue;
if (value.intvalue != 0) if (value.intvalue != 0)
continue; continue;
if (value.bound == ValueFlow::Value::Bound::Upper)
continue;
if (value.isImpossible() && value.bound != ValueFlow::Value::Bound::Lower)
continue;
if (value.isKnown() && value.bound != ValueFlow::Value::Bound::Point)
continue;
const Token* strlenTok = isStrlenOf(value.tokvalue, arrayTok); const Token* strlenTok = isStrlenOf(value.tokvalue, arrayTok);
if (!strlenTok) if (!strlenTok)
continue; continue;
ValueFlow::Value v = value; ValueFlow::Value v = value;
v.bound = ValueFlow::Value::Bound::Point;
v.valueType = ValueFlow::Value::ValueType::INT; v.valueType = ValueFlow::Value::ValueType::INT;
v.errorPath.emplace_back(strlenTok, "Return index of string to the first element that is 0"); v.errorPath.emplace_back(strlenTok, "Return index of string to the first element that is 0");
setTokenValue(tok, v, tokenlist->getSettings()); setTokenValue(tok, v, tokenlist->getSettings());
@ -8865,7 +8860,7 @@ void ValueFlow::setValues(TokenList *tokenlist, SymbolDatabase* symboldatabase,
std::size_t values = 0; std::size_t values = 0;
std::size_t n = 4; std::size_t n = 4;
while (n > 0 && values < getTotalValues(tokenlist)) { while (n > 0 && values != getTotalValues(tokenlist)) {
values = getTotalValues(tokenlist); values = getTotalValues(tokenlist);
valueFlowImpossibleValues(tokenlist, settings); valueFlowImpossibleValues(tokenlist, settings);
valueFlowSymbolicOperators(tokenlist, symboldatabase); valueFlowSymbolicOperators(tokenlist, symboldatabase);

17
test/testvalueflow.cpp
View File

@ -7585,6 +7585,23 @@ private:
" return 0;\n" " return 0;\n"
"}\n"; "}\n";
ASSERT_EQUALS(true, testValueOfXImpossible(code, 4U, 0)); ASSERT_EQUALS(true, testValueOfXImpossible(code, 4U, 0));
code = "int f(char *s, size_t i) {\n"
" if (i < strlen(s)) {\n"
" int x = s[i] != ' ';\n"
" return x;\n"
" }\n"
" return 0;\n"
"}\n";
ASSERT_EQUALS(false, testValueOfXKnown(code, 4U, 1));
code = "int f(char *s, size_t i) {\n"
" if (i == strlen(s)) {}\n"
" int x = s[i];\n"
" return x;\n"
"}\n";
ASSERT_EQUALS(false, testValueOfXKnown(code, 4U, 0));
ASSERT_EQUALS(true, testValueOfX(code, 4U, 0));
} }
void valueFlowSmartPointer() void valueFlowSmartPointer()