[Bug c/40235] New: -mstackrealign causes internal compiler error on x86_64

[olivier dot grisel at ensta dot org]

Compiling the following program named crash_stackrealign.c with content:

#include <stdlib.h>
#include <stdio.h>


int main(void) {
        float x = 42;
        return 0;
}

gives the following error when using the flag -mstackrealign on x86_64 (no
problem on i686 or without the mstackrealign flag):

ogrisel@blackbox:/tmp$ gcc -v -save-temps -mstackrealign -o  crash_stackrealign
crash_stackrealign.c
Using built-in specs.
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 4.3.3-5ubuntu4'
--with-bugurl=file:///usr/share/doc/gcc-4.3/README.Bugs
--enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --enable-shared
--with-system-zlib --libexecdir=/usr/lib --without-included-gettext
--enable-threads=posix --enable-nls --with-gxx-include-dir=/usr/include/c++/4.3
--program-suffix=-4.3 --enable-clocale=gnu --enable-libstdcxx-debug
--enable-objc-gc --enable-mpfr --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 4.3.3 (Ubuntu 4.3.3-5ubuntu4)
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-mstackrealign' '-o'
'crash_stackrealign' '-mtune=generic'
 /usr/lib/gcc/x86_64-linux-gnu/4.3.3/cc1 -E -quiet -v crash_stackrealign.c
-D_FORTIFY_SOURCE=2 -mstackrealign -mtune=generic -fpch-preprocess -o
crash_stackrealign.i
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring nonexistent directory
"/usr/lib/gcc/x86_64-linux-gnu/4.3.3/../../../../x86_64-linux-gnu/include"
ignoring nonexistent directory "/usr/include/x86_64-linux-gnu"
#include "..." search starts here:
#include <...> search starts here:
 /usr/local/include
 /usr/lib/gcc/x86_64-linux-gnu/4.3.3/include
 /usr/lib/gcc/x86_64-linux-gnu/4.3.3/include-fixed
 /usr/include
End of search list.
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-mstackrealign' '-o'
'crash_stackrealign' '-mtune=generic'
 /usr/lib/gcc/x86_64-linux-gnu/4.3.3/cc1 -fpreprocessed crash_stackrealign.i
-quiet -dumpbase crash_stackrealign.c -mstackrealign -mtune=generic -auxbase
crash_stackrealign -version -fstack-protector -ocrash_stackrealign.s
GNU C (Ubuntu 4.3.3-5ubuntu4) version 4.3.3 (x86_64-linux-gnu)
        compiled by GNU C version 4.3.3, GMP version 4.2.4, MPFR version 2.4.0.
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 67d7a81bea2b3850275b5f3aed53a5bf
crash_stackrealign.c: In function ‘main’:
crash_stackrealign.c:8: error: unrecognizable insn:
(insn 26 25 27 crash_stackrealign.c:5 (parallel [
            (set (reg/f:DI 7 sp)
                (and:SI (reg/f:DI 7 sp)
                    (const_int -16 [0xfffffffffffffff0])))
            (clobber (reg:CC 17 flags))
        ]) -1 (nil))
crash_stackrealign.c:8: internal compiler error: in insn_default_length, at
insn-attrtab.c:1346
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-4.3/README.Bugs> for instructions.


-- 
           Summary: -mstackrealign causes internal compiler error on x86_64
           Product: gcc
           Version: 4.3.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: olivier dot grisel at ensta dot org
  GCC host triplet: x86_64-linux-gnu
GCC target triplet: x86_64-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40235