Recent libstdc++-v3 regressions (PCHs related?!?)

[Paolo Carlini <paolo.carlini@oracle.com>]

Hi,

sorry it the issue is by now well known but... I see many libstdc++-v3 
regressions on at least x86_64-linux. When running the libstdc++-v3 
testsuite (which uses PCHs) one gets tons of new fails like the below. 
That's annoying, a lot of confusing noise.

Thanks!
Paolo.

PS: CC-ing two "random" ;) people lately very active.

///////////////////////////

FAIL: 17_intro/headers/c++200x/stdc++.cc (test for excess errors)
Excess errors:
/home/paolo/Gcc/svn-dirs/trunk-build/x86_64-unknown-linux-gnu/libstdc++-v3/include/bits/shared_ptr_base.h:567:2: 
internal compiler error: Segmentation fault
0xb2521f crash_signal
     /scratch/Gcc/svn-dirs/trunk/gcc/toplev.c:335
0xa747a7 gcc::pass_manager::gt_ggc_mx()
     /scratch/Gcc/svn-dirs/trunk/gcc/passes.c:201
0x9652b5 ggc_mark_root_tab
     /scratch/Gcc/svn-dirs/trunk/gcc/ggc-common.c:133
0x965600 ggc_mark_roots()
     /scratch/Gcc/svn-dirs/trunk/gcc/ggc-common.c:152
0x7c1f44 ggc_collect()
     /scratch/Gcc/svn-dirs/trunk/gcc/ggc-page.c:2077
0x836995 cgraph_finalize_function(tree_node*, bool)
     /scratch/Gcc/svn-dirs/trunk/gcc/cgraphunit.c:456
0x6e882f expand_or_defer_fn(tree_node*)
     /scratch/Gcc/svn-dirs/trunk/gcc/cp/semantics.c:3941
0x719104 maybe_clone_body(tree_node*)
     /scratch/Gcc/svn-dirs/trunk/gcc/cp/optimize.c:428
0x6e848f expand_or_defer_fn_1(tree_node*)
     /scratch/Gcc/svn-dirs/trunk/gcc/cp/semantics.c:3866
0x6e8808 expand_or_defer_fn(tree_node*)
     /scratch/Gcc/svn-dirs/trunk/gcc/cp/semantics.c:3936
0x5ce0ed instantiate_decl(tree_node*, int, bool)
     /scratch/Gcc/svn-dirs/trunk/gcc/cp/pt.c:19269
0x6096df instantiate_pending_templates(int)
     /scratch/Gcc/svn-dirs/trunk/gcc/cp/pt.c:19356
0x646b2a cp_write_global_declarations()
     /scratch/Gcc/svn-dirs/trunk/gcc/cp/decl2.c:4064

Thanks!
Paolo.