From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 10776 invoked by alias); 21 Feb 2005 21:44:46 -0000 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org Received: (qmail 10680 invoked by uid 48); 21 Feb 2005 21:44:36 -0000 Date: Tue, 22 Feb 2005 01:42:00 -0000 From: "jkohen at users dot sourceforge dot net" To: gcc-bugs@gcc.gnu.org Message-ID: <20050221214433.20126.jkohen@users.sourceforge.net> Reply-To: gcc-bugzilla@gcc.gnu.org Subject: [Bug c/20126] New: Inlined memcmp makes one argument null on entry X-Bugzilla-Reason: CC X-SW-Source: 2005-02/txt/msg02534.txt.bz2 List-Id: Hi, I found out a compiler bug triggered by compiling Python 2.3 with GCC 4.0 "pre5." I've been able to track it down to a small fragment which I'll attach below. The bug is a regression as GCC 3.4.4 20050203 produces a working application. This is the compiler's output and compilation command-line: Using built-in specs. Configured with: ../src/configure -v --enable-languages=c,c++,java,f95,objc,ada --prefix=/usr --libexecdir=/usr/lib --enable-shared --with-system-zlib --enable-nls --enable-threads=posix --without-included-gettext --program-suffix=-4.0 --enable-__cxa_atexit --enable-libstdcxx-allocator=mt --enable-clocale=gnu --enable-libstdcxx-debug --enable-java-gc=boehm --enable-java-awt=gtk --enable-mpfr x86_64-linux Thread model: posix gcc version 4.0.0 20050125 (experimental) (Debian 4.0-0pre5.0.0.1.gcc4) /usr/lib/gcc/x86_64-linux/4.0.0/cc1 -E -quiet -v ptest.c -mtune=k8 -Wall -Wstrict-prototypes -O3 -fpch-preprocess -o ptest.i ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux/4.0.0/../../../../x86_64-linux/include" #include "..." search starts here: #include <...> search starts here: /usr/local/include /usr/lib/gcc/x86_64-linux/4.0.0/include /usr/include End of search list. /usr/lib/gcc/x86_64-linux/4.0.0/cc1 -fpreprocessed ptest.i -quiet -dumpbase ptest.c -mtune=k8 -auxbase ptest -O3 -Wall -Wstrict-prototypes -version -o ptest.s GNU C version 4.0.0 20050125 (experimental) (Debian 4.0-0pre5.0.0.1.gcc4) (x86_64-linux) compiled by GNU C version 4.0.0 20050125 (experimental) (Debian 4.0-0pre5.0.0.1.gcc4). GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096 as -V -Qy --64 -o ptest.o ptest.s GNU ensamblador versión 2.15 (x86_64-linux) utilizando BFD versión 2.15 /usr/lib/gcc/x86_64-linux/4.0.0/collect2 --eh-frame-hdr -m elf_x86_64 -dynamic-linker /lib/ld-linux-x86-64.so.2 -o ptest /usr/lib/gcc/x86_64-linux/4.0.0/../../../../lib64/crt1.o /usr/lib/gcc/x86_64-linux/4.0.0/../../../../lib64/crti.o /usr/lib/gcc/x86_64-linux/4.0.0/crtbegin.o -L/usr/lib/gcc/x86_64-linux/4.0.0 -L/usr/lib/gcc/x86_64-linux/4.0.0 -L/usr/lib/gcc/x86_64-linux/4.0.0/../../../../lib64 -L/usr/lib/gcc/x86_64-linux/4.0.0/../../.. -L/lib/../lib64 -L/usr/lib/../lib64 ptest.o -lgcc --as-needed -lgcc_s --no-as-needed -lc -lgcc --as-needed -lgcc_s --no-as-needed /usr/lib/gcc/x86_64-linux/4.0.0/crtend.o /usr/lib/gcc/x86_64-linux/4.0.0/../../../../lib64/crtn.o In case the information is ambiguous, the compiler is a 64-bit binary generating 64-bit binaries. Please check http://lists.debian.org/debian-amd64/2005/02/msg00505.html for some comments I wrote on the relevant assembly output. -- Summary: Inlined memcmp makes one argument null on entry Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: normal Priority: P2 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: jkohen at users dot sourceforge dot net CC: gcc-bugs at gcc dot gnu dot org GCC build triplet: x86_64-linux GCC host triplet: x86_64-linux GCC target triplet: x86_64-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20126