[Bug c/44546] 4.5 ICE with -ffast-math -Os (compiling graphviz)

[chexum at gmail dot com]

------- Comment #3 from chexum at gmail dot com  2010-06-15 16:31 -------
/* minimal source showing (hopefully) the same ICE */
typedef struct { float *ewgts; } vtx_data; 
extern int whatever(vtx_data *);
float *compute_apsp_artifical_weights_packed (vtx_data * graph, int n)
{
  float *weights;

  weights = (float *) zmalloc (n * sizeof (float));
  weights[n] =
    whatever(graph) > graph[n].ewgts[n] ?
    whatever(graph) : graph[n].ewgts[n];
}

/* gcc -v -save-temps -Os -ffast-math ffmos.c */

Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/i586-pc-linux-gnu/4.5.0/lto-wrapper
Target: i586-pc-linux-gnu
Configured with: ..//configure --prefix=/usr --libexecdir=/usr/lib
--enable-shared --with-system-zlib
--enable-languages=c,c++,objc,java,ada,fortran --enable-threads
--enable-__cxa_atexit --enable-clocale=gnu --enable-libada --enable-shared
--with-ecj-jar=/usr/share/java/ecj.jar i586-pc-linux-gnu
Thread model: posix
gcc version 4.5.0 (GCC) 
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-Os' '-ffast-math' '-c'
'-mtune=pentium' '-march=pentium'
 /usr/lib/gcc/i586-pc-linux-gnu/4.5.0/cc1 -E -quiet -v ffmos.c -mtune=pentium
-march=pentium -ffast-math -Os -fpch-preprocess -o ffmos.i
ignoring nonexistent directory "/usr/local/include"
ignoring nonexistent directory
"/usr/lib/gcc/i586-pc-linux-gnu/4.5.0/../../../../i586-pc-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/lib/gcc/i586-pc-linux-gnu/4.5.0/include
 /usr/lib/gcc/i586-pc-linux-gnu/4.5.0/include-fixed
 /usr/include
End of search list.
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-Os' '-ffast-math' '-c'
'-mtune=pentium' '-march=pentium'
 /usr/lib/gcc/i586-pc-linux-gnu/4.5.0/cc1 -fpreprocessed ffmos.i -quiet
-dumpbase ffmos.c -mtune=pentium -march=pentium -auxbase ffmos -Os -version
-ffast-math -o ffmos.s
GNU C (GCC) version 4.5.0 (i586-pc-linux-gnu)
        compiled by GNU C version 4.5.0, GMP version 5.0.1, MPFR version 2.4.2,
MPC version 0.8.1
GGC heuristics: --param ggc-min-expand=98 --param ggc-min-heapsize=127922
GNU C (GCC) version 4.5.0 (i586-pc-linux-gnu)
        compiled by GNU C version 4.5.0, GMP version 5.0.1, MPFR version 2.4.2,
MPC version 0.8.1
GGC heuristics: --param ggc-min-expand=98 --param ggc-min-heapsize=127922
Compiler executable checksum: 7fe8daf58b4922cb9313351112738768
ffmos.c: In function &#8216;compute_apsp_artifical_weights_packed&#8217;:
ffmos.c:12:1: error: unrecognizable insn:
(jump_insn 59 58 47 2 ffmos.c:11 (set (pc)
        (if_then_else (lt (reg:CCFP 17 flags)
                (const_int 0 [0x0]))
            (label_ref:SI 45)
            (pc))) -1 (expr_list:REG_BR_PROB (const_int 2071 [0x817])
        (nil))
 -> 45)
ffmos.c:12:1: internal compiler error: in extract_insn, at recog.c:2103
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.


-- 

chexum at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |4.5.0
      Known to work|                            |4.3.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44546