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From: "pluto at agmk dot net" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug other/27417] New: wrong code or aliasing violation with missed diagnostic? Date: Thu, 04 May 2006 10:47:00 -0000 [thread overview] Message-ID: <bug-27417-7667@http.gcc.gnu.org/bugzilla/> (raw) inline float quickBinaryToFloat( unsigned const& in ) { return reinterpret_cast< float const& >( in ) ; } float foo( unsigned x ) { unsigned y = ( x * 2 ) + 1; return quickBinaryToFloat( y ); } [ wrong-code generated ] $ i486-gnu-linux-g++ bin2float.cpp -Wall -O2 -c -fomit-frame-pointer -m32 00000000 <foo(unsigned int)>: 0: 83 ec 10 sub $0x10,%esp 3: d9 44 24 0c flds 0xc(%esp) 7: 83 c4 10 add $0x10,%esp a: c3 ret [ correct code generated ] $ i486-gnu-linux-g++ bin2float.cpp -Wall -O2 -c -fomit-frame-pointer -m32 \ -fno-strict-aliasing 00000000 <foo(unsigned int)>: 0: 83 ec 10 sub $0x10,%esp 3: 8b 44 24 14 mov 0x14(%esp),%eax 7: 8d 44 00 01 lea 0x1(%eax,%eax,1),%eax b: 89 44 24 0c mov %eax,0xc(%esp) f: d9 44 24 0c flds 0xc(%esp) 13: 83 c4 10 add $0x10,%esp 16: c3 ret -- Summary: wrong code or aliasing violation with missed diagnostic? Product: gcc Version: 4.1.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: other AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: pluto at agmk dot net GCC build triplet: i486-linux GCC host triplet: i486-linux GCC target triplet: i486-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27417
next reply other threads:[~2006-05-04 10:47 UTC|newest] Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top 2006-05-04 10:47 pluto at agmk dot net [this message] 2006-05-04 11:58 ` [Bug other/27417] " rguenth at gcc dot gnu dot org 2006-05-04 12:08 ` pluto at agmk dot net 2006-05-04 14:00 ` rguenth at gcc dot gnu dot org 2006-05-05 15:10 ` pluto at agmk dot net
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