3.1 bootstrap failure with additional optimization flags

[Laurynas Biveinis]

On i686-pc-linux-gnu recent 3.1 compiler bootstrapped with CFLAGS="-O2 
-fomit-frame-pointer -fstrict-aliasing -march=pentiumpro" BOOT_CFLAGS="-O2
-fomit-frame-pointer -fstrict-aliasing -march=pentiumpro"

fails to build libstdc++:

/bin/sh ../libtool --tag disable-shared --tag CXX --tag disable-shared                --mode=compile /usr/local/cvs/gcc/obj/gcc/g++ -B/usr/local/cvs/gcc/obj/gcc/ -nostdinc++  -L/usr/local/cvs/gcc/obj/i686-pc-linux-gnu/libstdc++-v3/src -L/usr/local/cvs/gcc/obj/i686-pc-linux-gnu/libstdc++-v3/src/.libs -B/usr/local/i686-pc-linux-gnu/bin/ -B/usr/local/i686-pc-linux-gnu/lib/ -isystem /usr/local/i686-pc-linux-gnu/include -I../../../../libstdc++-v3/../gcc -I../../../../libstdc++-v3/../include 	-I../../../../libstdc++-v3/include -I../../../../libstdc++-v3/include/std -I../../../../libstdc++-v3/include/c_std -I../include 	 -I../../../../libstdc++-v3/libsupc++ 	         -g -O2 -fvtable-thunks -D_GNU_SOURCE -fno-implicit-templates 	-prefer-pic 	-Wall -Wno-format -W -Wwrite-strings -Winline  -fdiagnostics-show-location=once 	 	-ffunction-sections -fdata-sections  -g    -c ../../../../libstdc++-v3/libsupc++/exception_support.cc
/usr/local/cvs/gcc/obj/gcc/g++ -B/usr/local/cvs/gcc/obj/gcc/ -nostdinc++ -L/usr/local/cvs/gcc/obj/i686-pc-linux-gnu/libstdc++-v3/src -L/usr/local/cvs/gcc/obj/i686-pc-linux-gnu/libstdc++-v3/src/.libs -B/usr/local/i686-pc-linux-gnu/bin/ -B/usr/local/i686-pc-linux-gnu/lib/ -isystem /usr/local/i686-pc-linux-gnu/include -I../../../../libstdc++-v3/../gcc -I../../../../libstdc++-v3/../include -I../../../../libstdc++-v3/include -I../../../../libstdc++-v3/include/std -I../../../../libstdc++-v3/include/c_std -I../include -I../../../../libstdc++-v3/libsupc++ -g -O2 -fvtable-thunks -D_GNU_SOURCE -fno-implicit-templates -Wall -Wno-format -W -Wwrite-strings -Winline -fdiagnostics-show-location=once -ffunction-sections -fdata-sections -g -c ../../../../libstdc++-v3/libsupc++/exception_support.cc  -fPIC -DPIC -o exception_support.o
../../../../libstdc++-v3/libsupc++/exception_support.cc: In function 
   `cp_eh_info* __start_cp_handler()':
../../../../libstdc++-v3/libsupc++/exception_support.cc:124: warning: new 
   declaration `cp_eh_info* __start_cp_handler()'
../../../../libstdc++-v3/libsupc++/exception_support.cc:124: warning: ambiguates
   built-in declaration `cp_eh_info* __start_cp_handler()'
../../../../libstdc++-v3/libsupc++/exception_support.cc: In function `void 
   __check_null_eh_spec()':
../../../../libstdc++-v3/libsupc++/exception_support.cc:343: warning: `noreturn'
   function does return
../../../../libstdc++-v3/libsupc++/exception_support.cc: At global scope:
../../../../libstdc++-v3/libsupc++/exception_support.cc:388: Internal error: 
   Segmentation fault
Please submit a full bug report, with preprocessed source if appropriate.
See <URL: http://www.gnu.org/software/gcc/bugs.html > for instructions.
make[4]: *** [exception_support.lo] Error 1
make[4]: Leaving directory `/usr/local/cvs/gcc/obj/i686-pc-linux-gnu/libstdc++-v3/libsupc++'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/usr/local/cvs/gcc/obj/i686-pc-linux-gnu/libstdc++-v3'
make[2]: *** [all-recursive-am] Error 2
make[2]: Leaving directory `/usr/local/cvs/gcc/obj/i686-pc-linux-gnu/libstdc++-v3'
make[1]: *** [all-target-libstdc++-v3] Error 2
make[1]: Leaving directory `/usr/local/cvs/gcc/obj'
make: *** [bootstrap] Error 2