Improved handling of dereferences in CheckClass::noMemset(), fixing false negatives and false positives related to multidimensional arrays and arrays of pointers.

This commit is contained in:
PKEuS 2013-03-04 02:47:29 -08:00
parent dc65667cec
commit c24527dbde
2 changed files with 40 additions and 4 deletions

View File

@ -838,10 +838,28 @@ void CheckClass::noMemset()
typeTok = arg3->tokAt(3);
else if (Token::simpleMatch(arg3, "sizeof ( * this ) )") || Token::simpleMatch(arg1, "this ,")) {
type = findFunctionOf(arg3->scope());
} else if (Token::Match(arg1, "&| %var% ,")) {
const Variable *var = arg1->str() == "&" ? arg1->next()->variable() : arg1->variable();
if (var && (arg1->str() == "&" || var->isPointer() || var->isArray()))
type = var->type();
} else if (Token::Match(arg1, "&|*|%var%")) {
int derefs = 1;
for (;; arg1 = arg1->next()) {
if (arg1->str() == "&")
derefs--;
else if (arg1->str() == "*")
derefs++;
else
break;
}
const Variable *var = arg1->variable();
if (var && arg1->strAt(1) == ",") {
if (var->isPointer())
derefs--;
if (var->isArray())
derefs -= var->dimensions().size();
if (derefs == 0)
type = var->type();
}
}
// No type defined => The tokens didn't match

View File

@ -2305,6 +2305,24 @@ private:
" memset(a, 0, 100);\n"
"}");
ASSERT_EQUALS("", errout.str()); // #4460
checkNoMemset("struct C {\n"
" std::string s;\n"
"};\n"
"int foo() {\n"
" C* c1[10][10];\n"
" C* c2[10];\n"
" C c3[10][10];\n"
" memset(**c1, 0, 10);\n"
" memset(*c1, 0, 10);\n"
" memset(*c2, 0, 10);\n"
" memset(*c3, 0, 10);\n"
" memset(c2, 0, 10);\n"
" memset(c3, 0, 10);\n"
"}");
ASSERT_EQUALS("[test.cpp:8]: (error) Using 'memset' on struct that contains a 'std::string'.\n"
"[test.cpp:10]: (error) Using 'memset' on struct that contains a 'std::string'.\n"
"[test.cpp:11]: (error) Using 'memset' on struct that contains a 'std::string'.\n", errout.str());
}
void mallocOnClass() {