public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
From: "dickinsm at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c/44683] New: Optimization bug with copysign builtin Date: Sat, 26 Jun 2010 17:00:00 -0000 [thread overview] Message-ID: <bug-44683-16778@http.gcc.gnu.org/bugzilla/> (raw) Here's a minimal test-case: --------- int copysign_bug(double x) { if (x * 0.5 == x) return 1; else if (copysign(1.0, x) < 0.0) return 2; else return 3; } int main(void) { double x; x = -0.0; printf("copysign_bug(%.17g) = %d\n", x, copysign_bug(x)); x = 0.0; printf("copysign_bug(%.17g) = %d\n", x, copysign_bug(x)); return 0; } ------- I'm compiling and executing the above code (filename copysign_bug.c) on OpenSolaris build snv_134 running in Parallels on a Macbook Pro (Intel Core 2 Duo), using the following command line: gcc-4.4 -m64 -fno-inline -g -O3 copysign_bug.c -o copysign_bug && ./copysign_bug I get the results: copysign_bug(-0) = 3 copysign_bug(0) = 3 I was expecting to see the results: copysign_bug(-0) = 2 copysign_bug(0) = 3 I get the latter results if I omit the '-O3' flag, or if I compile with -fno-builtin-copysign and link with the math library. gcc build information: dickinsm@eratosthenes:~/trunk$ gcc-4.4 -v -save-temps -m64 -lm -fno-builtin-copysign -fno-inline -g copysign_bug.c Using built-in specs. Target: i386-pc-solaris2.11 Configured with: ../gcc-4.4.4/configure --prefix=/usr/local --program-suffix=-4.4 --with-mpfr-include=/usr/include/mpfr --with-gmp-include=/usr/include/gmp --with-as=/usr/bin/gas --with-gnu-as --with-ld=/usr/bin/ld --without-gnu-ld --enable-shared --enable-multilib --enable-languages=c,c++,objc Thread model: posix gcc version 4.4.4 (GCC) COLLECT_GCC_OPTIONS='-v' '-save-temps' '-m64' '-fno-builtin-copysign' '-fno-inline' '-g' '-mtune=generic' /usr/local/libexec/gcc/i386-pc-solaris2.11/4.4.4/cc1 -E -quiet -v -imultilib amd64 copysign_bug.c -m64 -mtune=generic -fno-builtin-copysign -fno-inline -g -fworking-directory -fpch-preprocess -o copysign_bug.i ignoring nonexistent directory "/usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/../../../../i386-pc-solaris2.11/include" #include "..." search starts here: #include <...> search starts here: /usr/local/include /usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/include /usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/include-fixed /usr/include End of search list. COLLECT_GCC_OPTIONS='-v' '-save-temps' '-m64' '-fno-builtin-copysign' '-fno-inline' '-g' '-mtune=generic' /usr/local/libexec/gcc/i386-pc-solaris2.11/4.4.4/cc1 -fpreprocessed copysign_bug.i -quiet -dumpbase copysign_bug.c -m64 -mtune=generic -auxbase copysign_bug -g -version -fno-builtin-copysign -fno-inline -o copysign_bug.s GNU C (GCC) version 4.4.4 (i386-pc-solaris2.11) compiled by GNU C version 4.4.4, GMP version 4.3.1, MPFR version 2.4.1-p5. GGC heuristics: --param ggc-min-expand=99 --param ggc-min-heapsize=131015 Compiler executable checksum: f408a824c22e56e60b321448197fb865 COLLECT_GCC_OPTIONS='-v' '-save-temps' '-m64' '-fno-builtin-copysign' '-fno-inline' '-g' '-mtune=generic' /usr/bin/gas -v -V -Qy --64 -s -o copysign_bug.o copysign_bug.s GNU assembler version 2.19 (i386-pc-solaris2.11) using BFD version (GNU Binutils) 2.19 COMPILER_PATH=/usr/local/libexec/gcc/i386-pc-solaris2.11/4.4.4/:/usr/local/libexec/gcc/i386-pc-solaris2.11/4.4.4/:/usr/local/libexec/gcc/i386-pc-solaris2.11/:/usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/:/usr/local/lib/gcc/i386-pc-solaris2.11/:/usr/ccs/bin/ LIBRARY_PATH=/usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/amd64/:/usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/../../../amd64/:/lib/amd64/:/usr/lib/amd64/:/usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/:/usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/../../../:/lib/:/usr/lib/ COLLECT_GCC_OPTIONS='-v' '-save-temps' '-m64' '-fno-builtin-copysign' '-fno-inline' '-g' '-mtune=generic' /usr/local/libexec/gcc/i386-pc-solaris2.11/4.4.4/collect2 -V -Y P,/lib/64:/usr/lib/64 -Qy /usr/lib/amd64/crt1.o /usr/lib/amd64/crti.o /usr/lib/amd64/values-Xa.o /usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/amd64/crtbegin.o -L/usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/amd64 -L/usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/../../../amd64 -L/lib/amd64 -L/usr/lib/amd64 -L/usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4 -L/usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/../../.. -lm copysign_bug.o -lgcc -lgcc_eh -lc -lgcc -lgcc_eh /usr/local/lib/gcc/i386-pc-solaris2.11/4.4.4/amd64/crtend.o /usr/lib/amd64/crtn.o ld: Software Generation Utilities - Solaris Link Editors: 5.11-1.1689 -- Summary: Optimization bug with copysign builtin Product: gcc Version: 4.4.4 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: dickinsm at gmail dot com GCC build triplet: i386-pc-solaris2.11 GCC host triplet: i386-pc-solaris2.11 GCC target triplet: i386-pc-solaris2.11 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44683
next reply other threads:[~2010-06-26 17:00 UTC|newest] Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top 2010-06-26 17:00 dickinsm at gmail dot com [this message] 2010-06-26 17:02 ` [Bug c/44683] " dickinsm at gmail dot com 2010-06-26 18:16 ` dickinsm at gmail dot com 2010-06-26 18:26 ` dickinsm at gmail dot com 2010-06-26 22:57 ` [Bug rtl-optimization/44683] " rguenth at gcc dot gnu dot org 2010-06-26 23:05 ` [Bug rtl-optimization/44683] [4.4/4.5/4.6 Regression] " rguenth at gcc dot gnu dot org 2010-06-27 3:05 ` hjl dot tools at gmail dot com 2010-06-27 8:50 ` [Bug tree-optimization/44683] " rguenth at gcc dot gnu dot org 2010-06-27 11:17 ` rguenth at gcc dot gnu dot org 2010-06-27 11:21 ` rguenth at gcc dot gnu dot org 2010-06-27 11:22 ` rguenth at gcc dot gnu dot org 2010-06-27 11:23 ` rguenth at gcc dot gnu dot org
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=bug-44683-16778@http.gcc.gnu.org/bugzilla/ \ --to=gcc-bugzilla@gcc.gnu.org \ --cc=gcc-bugs@gcc.gnu.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).