https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71020
Bug ID: 71020
Summary: SSA corruption: Unable to coalesce ssa_names 2 and 13
which are marked as MUST COALESCE.
Product: gcc
Version: 6.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: pdewacht at gmail dot com
Target Milestone: ---
This function triggers an internal compiler error. Reduced using C-Reduce from
a source file from FMSLogo.
$ cat ssa2.c
binary() {
double b = get();
_setjmp();
b = sqrt(b);
err_logo();
}
$ gcc-6 -O -w -c ssa2.c
Unable to coalesce ssa_names 2 and 13 which are marked as MUST COALESCE.
b_2(ab) and b_13(ab)
ssa2.c: In function ‘binary’:
ssa2.c:1:1: internal compiler error: SSA corruption
binary() {
^~~~~~
0xa90f9c fail_abnormal_edge_coalesce
../../src/gcc/tree-ssa-coalesce.c:1010
0xa90f9c coalesce_partitions
../../src/gcc/tree-ssa-coalesce.c:1411
0xa90f9c coalesce_ssa_name()
../../src/gcc/tree-ssa-coalesce.c:1895
0xa4798f remove_ssa_form
../../src/gcc/tree-outof-ssa.c:978
0xa4798f rewrite_out_of_ssa(ssaexpand*)
../../src/gcc/tree-outof-ssa.c:1202
0x69b2e0 execute
../../src/gcc/cfgexpand.c:6136
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <file:///usr/share/doc/gcc-6/README.Bugs> for instructions.
$ gcc-6 -v
Using built-in specs.
COLLECT_GCC=gcc-6
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/6/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 6.1.1-1'
--with-bugurl=file:///usr/share/doc/gcc-6/README.Bugs
--enable-languages=c,ada,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr
--program-suffix=-6 --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes
--with-default-libstdcxx-abi=new --enable-gnu-unique-object
--disable-vtable-verify --enable-libmpx --enable-plugin --with-system-zlib
--disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo
--with-java-home=/usr/lib/jvm/java-1.5.0-gcj-6-amd64/jre --enable-java-home
--with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-6-amd64
--with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-6-amd64
--with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar
--enable-objc-gc --enable-multiarch --with-arch-32=i686 --with-abi=m64
--with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic
--enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu
--target=x86_64-linux-gnu
Thread model: posix
gcc version 6.1.1 20160430 (Debian 6.1.1-1)
