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Fix #15114 FP shadowVariable (global variable prior to declaration) #8947

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Fix #15114 FP shadowVariable (global variable prior to declaration) #8947

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c5180d7
Update checkother.cpp
chrchr-github Oct 16, 2026
007ab4b
Update testother.cpp
chrchr-github Oct 16, 2026
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9 changes: 5 additions & 4 deletions lib/checkother.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -4226,7 +4226,7 @@ static const Token *findShadowed(const Scope *scope, const Variable& var, int li
if (!scope)
return nullptr;
for (const Variable &v : scope->varlist) {
if (scope->isExecutable() && v.nameToken()->linenr() > linenr)
if ((scope->isExecutable() || scope->type == ScopeType::eGlobal) && v.nameToken()->linenr() > linenr)

@dmcppcheck dmcppcheck Oct 16, 2026

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AI review

linenr() is compared without the file index. A global from an included header with a higher line number is now skipped, which is a new false negative compared with base. A function in a header that shadows a later global in the .c file still warns. The same-line case still warns too. For the global-scope case, consider !precedes(v.nameToken(), var.nameToken()), which the function lookup below already uses. eNamespace scopes have the same issue: namespace N { int f(){int i=0;return i;} int i=1; } still warns.

continue;
if (v.name() == var.name())
return v.nameToken();
Expand Down Expand Up @@ -4312,9 +4312,10 @@ void CheckOtherImpl::checkShadowVariables()
void CheckOtherImpl::shadowError(const Token *shadows, const std::string &shadowsType,
const Token *shadowed, const std::string &shadowedType)
{
ErrorPath errorPath;
errorPath.emplace_back(shadowed, "Shadowed " + shadowedType);
errorPath.emplace_back(shadows, "Shadow " + shadowsType);
ErrorPath errorPath{
{shadowed, "Shadowed " + shadowedType},
{shadows, "Shadow " + shadowsType}
};
const std::string &varname = shadows ? shadows->str() : shadowsType;
const std::string ShadowsType = char(std::toupper(shadowsType[0])) + shadowsType.substr(1);
const std::string ShadowedType = char(std::toupper(shadowedType[0])) + shadowedType.substr(1);
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7 changes: 7 additions & 0 deletions test/testother.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -13520,6 +13520,13 @@ class TestOther : public TestFixture {

check("struct S { void g(float f) {} void f() {} };\n");
ASSERT_EQUALS("[test.cpp:1:36] -> [test.cpp:1:25]: (style) Argument 'f' shadows outer function [shadowFunction]\n", errout_str());

check("int f() {\n" // #15114
" int i = 0;\n"
" return i;\n"
"}\n"
"int i = 1;\n");
ASSERT_EQUALS("", errout_str());
}

void knownArgument() {
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