Attached program is mktime() test usually runs by configure scripts. This test behaves badly (terminates with SIGALRM) if compiled with '-O2', but works as expected when compiled with '-O2 -fno-tree-vrp'.
I'm able to reproduce it on two systems: 1) x86_64 Fedora 8, kernel is 2.6.24.3, gcc 4.3 configured as: Using built-in specs. Target: x86_64-redhat-linux Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-languages=c,c++,objc,obj-c++,java,fortran,ada --enable-java-awt=gtk --disable-dssi --enable-plugin --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-1.5.0.0/jre --enable-libgcj-multifile --enable-java-maintainer-mode --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --disable-libjava-multilib --with-cpu=generic --build=x86_64-redhat-linux Thread model: posix gcc version 4.3.0 20080307 (Red Hat 4.3.0-2) (GCC) 2) i386 FreeBSD 7.0 (7.0-STABLE), gcc 4.3 configured with: Using built-in specs. Target: i386-unknown-freebsd7.0 Configured with: ../gcc-4.3.0/configure --program-suffix=43 --prefix=/usr/local --enable-checking=none --enable-multilib --enable-__cxa_atexit --enable-threads=posix --enable-languages=c,c++ --disable-nls --with-cpu=pentium4 --with-system-zlib Thread model: posix gcc version 4.3.0 (GCC) -- Summary: Option '-ftree-vrp' looks broken with '-O2' Product: gcc Version: 4.3.0 Status: UNCONFIRMED Severity: major Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: dmantipov at yandex dot ru GCC build triplet: x86_64-redhat-linux GCC host triplet: x86_64-redhat-linux GCC target triplet: x86_64-redhat-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35581
