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From: "mikulas at artax dot karlin dot mff dot cuni dot cz" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/40906] New: Wrong code generated for push of long double Date: Wed, 29 Jul 2009 17:04:00 -0000 [thread overview] Message-ID: <bug-40906-1600@http.gcc.gnu.org/bugzilla/> (raw) Hi. Try this program: #include <stdlib.h> void f(long double a) { if (a != 1.0) abort(); } int g(long double b) { f(b); return 0; } int main(void) { g(1.0); return 0; } Compile it with "-O2 -mpush-args -mno-accumulate-outgoing-args -fomit-frame-pointer -fno-inline" In gcc 4.3.2 it works, in gcc-4.4.1 it aborts. If you add -m128bit-long-double, both gcc 4.3 and 4.4 fail. The reason is that push of long double in the function "g" is badly generated --- it is pushing value that is already on the stack and while it is pushing it, the stack pointer changes. Gcc tries to compensate for it, but the code is buggy and it ends up pushing wrong words. -- Summary: Wrong code generated for push of long double Product: gcc Version: 4.4.1 Status: UNCONFIRMED Severity: major Priority: P3 Component: rtl-optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: mikulas at artax dot karlin dot mff dot cuni dot cz GCC build triplet: i686-pc-linux-gnu GCC host triplet: i686-pc-linux-gnu GCC target triplet: i686-pc-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40906
next reply other threads:[~2009-07-29 17:04 UTC|newest] Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top 2009-07-29 17:04 mikulas at artax dot karlin dot mff dot cuni dot cz [this message] 2009-07-29 17:07 ` [Bug rtl-optimization/40906] " mikulas at artax dot karlin dot mff dot cuni dot cz 2009-07-29 18:15 ` [Bug target/40906] " rguenth at gcc dot gnu dot org 2009-08-05 14:42 ` uros at gcc dot gnu dot org 2009-08-05 18:05 ` uros at gcc dot gnu dot org 2009-08-05 21:17 ` uros at gcc dot gnu dot org 2009-08-05 21:19 ` ubizjak at gmail dot com
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