-frtl-abstract-sequences broken?

[Laurent GUERBY <laurent at guerby dot net>]

Hi,

It looks like the tests for -frtl-abstract-sequences are either skipped
or xfailed for a long list of platforms:

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33642
"unrecognizable insn for -frtl-abstract-sequences"
<<
Almost any source file compiled for any of a large number of targets
(powerpc*-*, arm-eabi, hppa-linux, mipsel-linux, s390*-linux, sh*-*, sparc*-*)
with -O2 -frtl-abstract-sequences results in the following:

bug1.c: In function âfooâ:
bug1.c:8: error: unrecognizable insn:
(insn 28bug1.c:8: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

The testcase used here:

int foo (void)
{
  return 0;
}
>>

gcc/testsuite/gcc.c-torture/compile/pr11832.c
/* { dg-do compile } */
/* Currently ICEs for Alpha, IA64, HPPA, MIPS, CRIS, Xtensa, PowerPC, SH and SPARC; see PR33642.  */
/* { dg-xfail-if "PR33642" { alpha*-*-* hppa*-*-* mips*-*-* powerpc*-*-* cris-*-* crisv32-*-* ia64-*-* xtensa*-*-* sh*-*-* sparc*-*-* s390*-*-* } { "*" } { "" } } */
/* Currently ICEs for (x86 && ilp32 && pic).  */
/* { dg-xfail-if "PR33642/36240" { { i?86-*-* x86_64-*-* } && { ilp32 && { ! nonpic } } } { "*" } { "" } } */


I was about to add arm*-*-* but there are other reports about this flag
(not exhaustive, just based on summary):

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30121
"ICE on frtl-abstract-sequences"

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31549
"Documentation for -frtl-abstract-sequences is in the wrong place"

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36240
"PIC and -frtl-abstract-sequences"

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38694
"gcc.c-torture/compile/pr11832.c and pr33009.c -frtl-abstract-sequences
ICE on arm-linux-gnueabi on 4.3.2 and trunk"

What should be done about this optimization for 4.4 and 4.5? Is there
anyone trying to fix its shortcomings?

Thanks in advance,

Laurent