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Fix #13812 value potentially truncated in ValueFlowAnalyzer::evaluteInt() #8482

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Merged
chrchr-github merged 4 commits into from
Apr 23, 2026
+11 −3
Merged

Fix #13812 value potentially truncated in ValueFlowAnalyzer::evaluteInt() #8482

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3f15b8e
Update vf_analyzers.cpp
chrchr-github Apr 23, 2026
4569295
Update vf_analyzers.cpp
chrchr-github Apr 23, 2026
35e94c2
Update testvalueflow.cpp
chrchr-github Apr 23, 2026
6ff10a2
Update vf_analyzers.cpp
chrchr-github Apr 23, 2026
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4 changes: 2 additions & 2 deletions lib/vf_analyzers.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -676,7 +676,7 @@ struct ValueFlowAnalyzer : Analyzer {
std::vector<MathLib::bigint> evaluateInt(const Token* tok, F getProgramMemory) const
{
if (const ValueFlow::Value* v = tok->getKnownValue(ValueFlow::Value::ValueType::INT))
return {static_cast<int>(v->intvalue)};
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return {v->intvalue};
std::vector<MathLib::bigint> result;
ProgramMemory pm = getProgramMemory();
if (Token::Match(tok, "&&|%oror%")) {
Expand Down Expand Up @@ -717,7 +717,7 @@ struct ValueFlowAnalyzer : Analyzer {
ProgramMemory pm = pms.get(tok, ctx, getProgramState());
MathLib::bigint out = 0;
if (pm.getContainerEmptyValue(tok->exprId(), out))
return {static_cast<int>(out)};
return {out};
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@chrchr-github chrchr-github Apr 23, 2026

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Harmless but unnecessary (out is effectively a bool).

return {};
}
return {};
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10 changes: 9 additions & 1 deletion test/testvalueflow.cpp
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Expand Up @@ -320,7 +320,7 @@ class TestValueFlow : public TestFixture {
}

#define testValueOfX(...) testValueOfX_(__FILE__, __LINE__, __VA_ARGS__)
bool testValueOfX_(const char* file, int line, const char code[], unsigned int linenr, int value, const Settings *s = nullptr) {
bool testValueOfX_(const char* file, int line, const char code[], unsigned int linenr, MathLib::bigint value, const Settings *s = nullptr) {
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@firewave firewave Apr 23, 2026

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This smells like it should have been reported by one of the compiler warnings we have disabled...

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@chrchr-github chrchr-github Apr 23, 2026

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Maybe, but so far all tests used only values in the int range.

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@firewave firewave Apr 23, 2026

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The comparison between value and Value::intvalue below should have triggered one for sure. That would be a different one from the implicit conversion the call would have done.

const Settings *settings1 = s ? s : &settings;

// Tokenize..
Expand Down Expand Up @@ -3973,6 +3973,14 @@ class TestValueFlow : public TestFixture {
" return x;\n"
"}";
ASSERT_EQUALS(true, testValueOfX(code, 4U, 246));

code = "int64_t f() {\n"
" const int64_t val = 1LL << 33;\n"
" int64_t x = val;\n"
" x += val;\n"
" return x;\n"
"}";
ASSERT_EQUALS(true, testValueOfX(code, 5U, 1LL << 34));
}

void valueFlowForwardCorrelatedVariables() {
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