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Fix #14949: FP leakNoVarFunctionCall when passing resource to constructor#8765

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Fix #14949: FP leakNoVarFunctionCall when passing resource to constructor #8765

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09d0cc4
Fix #14949: FP when passing resource to ctor
Jul 29, 2026
960641a
remove temp comment
Jul 29, 2026
9590471
remove else after continue
Jul 30, 2026
b8feb14
revert check for alloc in ctor
Jul 30, 2026
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28 changes: 13 additions & 15 deletions lib/checkmemoryleak.cpp
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Original file line numberDiff line numberDiff line change
Expand Up@@ -1046,22 +1046,20 @@ void CheckMemoryLeakNoVarImpl::checkForUnreleasedInputArgument(const Scope *scop
const AllocType alloc = getAllocationType(arg, 0);
if (alloc == No)
continue;
if (alloc == New || alloc == NewArray) {
const Token* typeTok = arg->next();
bool bail = !typeTok->isStandardType() &&
(!typeTok->valueType() ||
(typeTok->valueType()->type < ValueType::Type::SMART_POINTER &&
typeTok->valueType()->type != ValueType::Type::POD)) &&
!mSettings.library.detectContainerOrIterator(typeTok) &&
!mSettings.library.podtype(typeTok->expressionString());
if (bail && typeTok->type() && typeTok->type()->classScope &&
typeTok->type()->classScope->numConstructors == 0 &&
typeTok->type()->classScope->getDestructor() == nullptr) {
bail = false;
}
if (bail)
continue;
const Token* typeTok = arg->next();

@ludviggunneludviggunneAug 5, 2026

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I'm not so sure typeTok is meaningful if it's not preceded by new. I believe in the test cases it's just a (. If we want to bail out here I think it's enough to determine that it's passed to a constructor.

@aadanenaadanenAug 5, 2026•
edited
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I don't understand. Using git blame I traced those lines back to 23deadb370 and 54b9fa5523. It seems to me like they are there for a reason. Maybe they are unnecessary, but I feel that should be a separate PR.

Edit: nevermind sorry I see the issue. I will see about reducing these checks.

@aadanenaadanenAug 5, 2026•
edited
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I tried removing different subsets of the checks and something like

if (tok->function() && !tok->function()->isConstructor())
continue;

based on your suggestion about checking if it's passed to a constructor but wasn't able to pass all test cases. I've got to do some other work so likely won't be able to solve this today. It might be a bit beyond my limited knowledge as most of my cppcheck hacking has been focused on the front end.

bool bail = !typeTok->isStandardType() &&
(!typeTok->valueType() ||
(typeTok->valueType()->type < ValueType::Type::SMART_POINTER &&
typeTok->valueType()->type != ValueType::Type::POD)) &&
!mSettings.library.detectContainerOrIterator(typeTok) &&
!mSettings.library.podtype(typeTok->expressionString());
if (bail && typeTok->type() && typeTok->type()->classScope &&
typeTok->type()->classScope->numConstructors == 0 &&
typeTok->type()->classScope->getDestructor() == nullptr) {
bail = false;
}
if (bail)
continue;
if (isReopenStandardStream(arg))
continue;
if (tok->function()) {
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17 changes: 17 additions & 0 deletions test/testmemleak.cpp
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Original file line numberDiff line numberDiff line change
Expand Up@@ -2628,6 +2628,23 @@ class TestMemleakNoVar : public TestFixture {
"[test.cpp:7:12]: (error) Allocation with f2, assert doesn't release it. [leakNoVarFunctionCall]\n"
"[test.cpp:8:12]: (error) Allocation with f3, assert doesn't release it. [leakNoVarFunctionCall]\n",
errout_str());
check("struct S {\n"
" explicit S(int fd) {\n"
" m_fd = fd;\n"
" }\n"
" ~S() {\n"
" if (m_fd >= 0)\n"
" close(m_fd); \n"
" }\n"
" int m_fd = -1;\n"
"};\n"
"S g(char *name) {\n"
" return S(mkostemp(name, 0));\n"
"}\n"
"void f(char* ptr) {\n"
" S s = g(ptr);\n"
"}\n");
ASSERT_EQUALS("", errout_str());
}

void missingAssignment() {
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