[Bug tree-optimization/55018] New: CDDCE phase is too aggressive

[nmorey at kalray dot eu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55018

             Bug #: 55018
           Summary: CDDCE phase is too aggressive
    Classification: Unclassified
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: nmorey@kalray.eu


Created attachment 28502
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28502
Source code to reproduce the bug

When compiling the attached source file with
 gcc  -O3 tmp.c -c

All the code from Sender_Signal function is removed during cddce2 phase.
The generated code only contains an empty infinite loop which is wrong.

Seen on:
Using built-in specs.
COLLECT_GCC=/usr/bin/gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-redhat-linux/4.7.2/lto-wrapper
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 --disable-build-with-cxx
--disable-build-poststage1-with-cxx --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-gnu-unique-object
--enable-linker-build-id --with-linker-hash-style=gnu
--enable-languages=c,c++,objc,obj-c++,java,fortran,ada,go,lto --enable-plugin
--enable-initfini-array --enable-java-awt=gtk --disable-dssi
--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-ppl --with-cloog --with-tune=generic --with-arch_32=i686
--build=x86_64-redhat-linux
Thread model: posix
gcc version 4.7.2 20120921 (Red Hat 4.7.2-2) (GCC)