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Fix #14520: false positive: passedByValue on declaration with const #8460

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Fix #14520: false positive: passedByValue on declaration with const #8460

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29760ce
update test
ludviggunne Apr 16, 2026
0357bb6
add test
ludviggunne Apr 16, 2026
1380219
fix
ludviggunne Apr 16, 2026
86b80d3
Update test/testother.cpp
ludviggunne Apr 21, 2026
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15 changes: 15 additions & 0 deletions lib/checkother.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1591,6 +1591,21 @@ void CheckOther::checkPassByReference()
if (var->isArray() && (!var->isStlType() || Token::simpleMatch(var->nameToken()->next(), "[")))
continue;

if (var->isArgument()) {
const Token *tok = var->typeStartToken();
for (; tok; tok = tok->next()) {
if (Token::simpleMatch(tok, "(")) {
tok = tok->link();
continue;
}
if (Token::simpleMatch(tok, ")"))
break;
}

if (Token::simpleMatch(tok, ") ;"))
continue;
}

const bool isConst = var->isConst();
if (isConst) {
passedByValueError(var, inconclusive, isRangeBasedFor);
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11 changes: 11 additions & 0 deletions test/testother.cpp
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Expand Up @@ -2910,6 +2910,9 @@ class TestOther : public TestFixture {
ASSERT_EQUALS("", errout_str());

check("struct X { int a[5]; }; void f(const X v);");
ASSERT_EQUALS("", errout_str());

check("struct X { int a[5]; }; void f(const X v) { (void) v; }");
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ASSERT_EQUALS("[test.cpp:1:40]: (performance) Function parameter 'v' should be passed by const reference. [passedByValue]\n", errout_str());

check("extern \"C\" { struct X { int a[5]; }; void f(const X v); }");
Expand Down Expand Up @@ -4108,6 +4111,14 @@ class TestOther : public TestFixture {
" if (*pp) {}\n"
"}\n");
ASSERT_EQUALS("", errout_str());

check("class C {\n"
"public:\n"
" explicit C(const std::string s);\n"
"private:\n"
" std::string _s;\n"
"};\n");
ASSERT_EQUALS("", errout_str());
}

void constParameterCallback() {
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