Static analyzer fails to track path invariants involving bitmasks. #10571
Description
| Bugzilla Link | 10199 |
| Resolution | DUPLICATE |
| Resolved on | Apr 03, 2014 13:39 |
| Version | trunk |
| OS | MacOS X |
| Reporter | LLVM Bugzilla Contributor |
| CC | @belkadan |
Extended Description
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void f(unsigned);
void g(unsigned, unsigned);
void
f(unsigned flags)
{
unsigned inbytes, outbytes;
if ((flags & 1) != 0)
inbytes = outbytes = 0;
if ((flags & 1) != 0)
g(inbytes, outbytes);
}
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Yields:
%%%
x.cc:13:3: warning: Function call argument is an uninitialized value
g(inbytes, outbytes);
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Eliminating the bitmask (i.e. "if (flags != 0)") the analyzer detects that inbytes and outbytes are always initialized.
Version:
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clang version 3.0 (trunk 133679)
Target: x86_64-apple-darwin10.7.0
Thread model: posix
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