aa454dda2e
Previously `LValueToRValueBitCast`s were modeled in the same way how
a regular `BitCast` was. However, this should not produce an l-value.
Modeling bitcasts accurately is tricky, so it's probably better to
model this expression by binding a fresh conjured value.
The following code should not result in a diagnostic:
```lang=C++
__attribute__((always_inline))
static inline constexpr unsigned int_castf32_u32(float __A) {
return __builtin_bit_cast(unsigned int, __A); // no-warning
}
```
Previously, it reported
`Address of stack memory associated with local variable '__A' returned
to caller [core.StackAddressEscape]`.
Differential Revision: https://reviews.llvm.org/D105017
Reviewed by: NoQ, vsavchenko
33 lines
1.0 KiB
C++
33 lines
1.0 KiB
C++
// RUN: %clang_analyze_cc1 -triple x86_64-unknown-unknown -verify %s \
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// RUN: -analyzer-checker=core,debug.ExprInspection
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template <typename T> void clang_analyzer_dump(T);
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__attribute__((always_inline)) static inline constexpr unsigned int _castf32_u32(float __A) {
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return __builtin_bit_cast(unsigned int, __A); // no-warning
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}
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void test(int i) {
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_castf32_u32(42);
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float f = 42;
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// Loading from a floating point value results in unknown,
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// which later materializes as a conjured value.
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auto g = __builtin_bit_cast(unsigned int, f);
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clang_analyzer_dump(g);
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// expected-warning-re@-1 {{{{^conj_\$[0-9]+{unsigned int,}}}}
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auto g2 = __builtin_bit_cast(unsigned int, 42.0f);
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clang_analyzer_dump(g2);
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// expected-warning-re@-1 {{{{^conj_\$[0-9]+{unsigned int,}}}}
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auto g3 = __builtin_bit_cast(unsigned int, i);
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clang_analyzer_dump(g3);
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// expected-warning-re@-1 {{{{^reg_\$[0-9]+<int i>}}}}
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auto g4 = __builtin_bit_cast(unsigned long, &i);
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clang_analyzer_dump(g4);
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// expected-warning@-1 {{&i [as 64 bit integer]}}
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}
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