[Bug c/25491] New: gcc segfaults compiling very long expressions

[geckosenator at gmail dot com]

I was writing a program that evaluates an operator tree with variables
constants and operators.  Rather than recursively iterate the tree many times
for different variable values to evaluate it.. I printed the tree into a source
file, compiled it as a shared library with gcc and dynamically linked it and
call the function.  In my case this is a much faster solution.. unless the tree
is too big:

$ /usr/bin/gcc -shared -o libevaleqn.so evaleqn.c
evaleqn.c:2:9: warning: null character(s) ignored
gcc: Internal error: Segmentation fault (program cc1)
Please submit a full bug report.
See http://bugs.gentoo.org/> for instructions.

For smaller sizes it compiles fine.  I'm guessing this is a limitation on the
length of expressions supported by gcc.

I tested this on x86_64 (gcc 3.4.4) and i686 (gcc 3.4.4 and 3.3.6) and the
results are the same.


-- 
   Summary: gcc segfaults compiling very long expressions
   Product: gcc
   Version: 3.4.4
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: geckosenator at gmail dot com
 GCC build triplet: i686-pc-linux
  GCC host triplet: i686-pc-linux
GCC target triplet: i686-pc-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25491

[Bug c/25491] gcc segfaults compiling very long expressions

[geckosenator at gmail dot com]

--- Comment #1 from geckosenator at gmail dot com  2005-12-19 02:27 ---
Created an attachment (id=10531)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=10531&action=view)
bzip2 compressed file that produces gcc segfault


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25491

[Bug c/25491] gcc segfaults compiling very long expressions

[geckosenator at gmail dot com]

--- Comment #3 from geckosenator at gmail dot com  2005-12-19 13:31 ---
(In reply to comment #2)
> Works with 4.1, needs 300MB ram and about 10s (-O0).
> Same for 4.0.x.
> Works for 3.4, too, with 178MB but takes a bit longer to compile.
> 
> Are you sure you tried compiling without optimization?
> 

I have tested it myself with gcc 4.0.2 and it worked.  I'm now told this isn't
a problem on gcc 4.x.. so I'm no longer sure if I should report it as a valid
bug.

I have had other people test this on gcc 3.x with both failure and success.  I
think it depends how gcc is installed. 

I was not using optimizations when I tested it.

thanks


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25491