[Bug rtl-optimization/63325] New: [5.0 regression] ICE fold check: original tree changed by fold

["dimhen at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63325

            Bug ID: 63325
           Summary: [5.0 regression] ICE fold check: original tree changed
                    by fold
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dimhen at gmail dot com

r215401 PASS
r215427, r215444 FAIL

Fedora 20 / x86_64

$ configure --enable-checking=fold
$ make
[...]
/home/dimhen/build/gcc_current/./gcc/xgcc
-B/home/dimhen/build/gcc_current/./gcc/
-B/usr/local/gcc_current/x86_64-unknown-linux-gnu/bin/
-B/usr/local/gcc_current/x86_64-unknown-linux-gnu/lib/ -isystem
/usr/local/gcc_current/x86_64-unknown-linux-gnu/include -isystem
/usr/local/gcc_current/x86_64-unknown-linux-gnu/sys-include    -g -O2 -m32 -O2 
-g -O2 -DIN_GCC    -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual
-Wno-format -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition 
-isystem ./include   -fpic -mlong-double-80 -g -DIN_LIBGCC2 -fbuilding-libgcc
-fno-stack-protector   -fpic -mlong-double-80 -I. -I. -I../../.././gcc
-I/home/dimhen/src/gcc_current/libgcc -I/home/dimhen/src/gcc_current/libgcc/.
-I/home/dimhen/src/gcc_current/libgcc/../gcc
-I/home/dimhen/src/gcc_current/libgcc/../include
-I/home/dimhen/src/gcc_current/libgcc/config/libbid -DENABLE_DECIMAL_BID_FORMAT
-DHAVE_CC_TLS  -DUSE_TLS -o generic-morestack.o -MT generic-morestack.o -MD -MP
-MF generic-morestack.dep  -c
/home/dimhen/src/gcc_current/libgcc/generic-morestack.c -fvisibility=hidden
-DHIDE_EXPORTS
/home/dimhen/src/gcc_current/libgcc/generic-morestack.c: In function
'__morestack_block_signals':
/home/dimhen/src/gcc_current/libgcc/generic-morestack.c:675:3: internal
compiler error: fold check: original tree changed by fold
   else if (pthread_sigmask)
   ^
0x9e0512 fold_check_failed
    /home/dimhen/src/gcc_current/gcc/fold-const.c:14554
0x9e0407 fold(tree_node*)
    /home/dimhen/src/gcc_current/gcc/fold-const.c:14531
0x6f9719 c_fully_fold_internal
    /home/dimhen/src/gcc_current/gcc/c-family/c-common.c:1309
0x6f8865 c_fully_fold(tree_node*, bool, bool*)
    /home/dimhen/src/gcc_current/gcc/c-family/c-common.c:1101
0x6d4ada c_parser_condition
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:5052
0x6d4b38 c_parser_paren_condition
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:5069
0x6d4f01 c_parser_if_statement
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:5170
0x6d43b9 c_parser_statement_after_labels
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:4888
0x6d4e61 c_parser_else_body
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:5144
0x6d4f8d c_parser_if_statement
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:5178
0x6d43b9 c_parser_statement_after_labels
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:4888
0x6d3e76 c_parser_compound_statement_nostart
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:4650
0x6d38a1 c_parser_compound_statement
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:4487
0x6ce7d2 c_parser_declaration_or_fndef
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:1946
0x6cd462 c_parser_external_declaration
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:1416
0x6cd0e5 c_parser_translation_unit
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:1303
0x6ed98a c_parse_file()
    /home/dimhen/src/gcc_current/gcc/c/c-parser.c:14322
0x7533a7 c_common_parse_file()
    /home/dimhen/src/gcc_current/gcc/c-family/c-opts.c:1043
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
make[5]: *** [generic-morestack.o] Error 1
make[5]: Leaving directory
`/home/dimhen/build/gcc_current/x86_64-unknown-linux-gnu/32/libgcc'
make[4]: *** [multi-do] Error 1
make[4]: Leaving directory
`/home/dimhen/build/gcc_current/x86_64-unknown-linux-gnu/libgcc'
make[3]: *** [all-multi] Error 2
make[3]: Leaving directory
`/home/dimhen/build/gcc_current/x86_64-unknown-linux-gnu/libgcc'
make[2]: *** [all-stage1-target-libgcc] Error 2
make[2]: Leaving directory `/home/dimhen/build/gcc_current'
make[1]: *** [stage1-bubble] Error 2
make[1]: Leaving directory `/home/dimhen/build/gcc_current'
make: *** [all] Error 2