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[Mingw-notify] [ mingw-Bugs-2535618 ] requires -O2 to be explicitly --lots-of-options
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From: SourceForge.net <no...@so...> - 2009-01-26 18:28:59
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Bugs item #2535618, was opened at 2009-01-25 16:42 Message generated for change (Comment added) made by gderosa You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=102435&aid=2535618&group_id=2435 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: gcc Group: None Status: Open Resolution: None Priority: 5 Private: No Submitted By: Guido De Rosa (gderosa) Assigned to: Nobody/Anonymous (nobody) Summary: requires -O2 to be explicitly --lots-of-options Initial Comment: On Windows XP SP2 $ gcc -v Reading specs from c:/MinGW/bin/../lib/gcc/mingw32/3.4.5/specs Configured with: ../gcc-3.4.5-20060117-3/configure --with-gcc --with-gnu-ld --with-gnu-as --host=mingw32 --target=mingw32 --prefix=/mingw --enable-threads --disable-nls --enable-languages=c,c++,f77,ada,objc,java --disable-win32-registry --disable-shared --enable-sjlj-exceptions --enable-libgcj --disable-java-awt --without-x --enable-java-gc=boehm --disable-libgcj-debug --enable-interpreter --enable-hash-synchronization --enable-libstdcxx-debug Thread model: win32 gcc version 3.4.5 (mingw-vista special r3) The problem arose here: http://lists.gnu.org/archive/html/bug-gsl/2006-09/msg00004.html and I found it disappears when -O2 optimization flag is explicitly expanded into --lots-of-optimization-flags which are documented here: http://gcc.gnu.org/onlinedocs/gcc-3.4.5/gcc/Optimize-Options.html I also suggested this as a workaround to the GSL mailing list: http://lists.gnu.org/archive/html/help-gsl/2009-01/msg00053.html Attached files: *.i : preprocessor output of gsl-1-12/monte/*.c *.s.orig : assembly code produced by gcc -O2 -mms-bitfields -march=i686 -c *.c *.s : the same as above, but with -fdefer-pop -fmerge-constants -fthread-jumps etc. etc. instead of -O2 gsl-1.12 was downloaded from ftp://ftp.gnu.org/gnu/gsl/gsl-1.2.tar.gz ---------------------------------------------------------------------- >Comment By: Guido De Rosa (gderosa) Date: 2009-01-26 19:28 Message: It works! Thanks. So: should this be considered as a MinGW bug or a GSL bug? ---------------------------------------------------------------------- Comment By: Danny Smith (dannysmith) Date: 2009-01-26 07:36 Message: This is an excess precision problem. Add -ffloat-store to CFLAGS to force truncation of floating point data to 53-bit mantissa doubles. Danny ---------------------------------------------------------------------- Comment By: Guido De Rosa (gderosa) Date: 2009-01-25 17:43 Message: mailing list reference: http://comments.gmane.org/gmane.comp.gnu.mingw.user/28722 ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=102435&aid=2535618&group_id=2435 |