[Bug c/93108] mmix generates invalid assembly on newlib (-fstack-protector-strong -ffunction-sections): internal error: fixup not contained within frag

[slyfox at inbox dot ru]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93108

--- Comment #1 from Sergei Trofimovich <slyfox at inbox dot ru> ---
Created attachment 47573
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47573&action=edit
min-bug.c

The bug initially discovered on gcc-9.2.0. creduce managed to shrink it down to
min-bug.c.

On it the error and generated file look like:

$ ./xgcc -B. -fstack-protector-strong -c min-bug.c -o min-bug.o -save-temps
min-bug.c: Assembler messages:
min-bug.c:430: Error: internal error: fixup not contained within frag

$ nl -ha min-bug.s

   426          BZ $0,L:4
   427          SLU $0,$2,32
   428          SR $0,$0,32
   429          CMP $0,$0,0
   430          BZ $0,L:4
   431          GETA $2,LC:0
   432          STOU $2,h
   433  L:4     IS @
   434          SUBU $0,$253,16
   435          LDO $1,$0,0
   436          LDO $0,__stack_chk_guard
   437          CMP $0,$1,$0
   438          BZ $0,L:28
   439          PUSHJ $8,__stack_chk_fail
   440  L:28    IS @
   441          SET $0,$2
   442          INCL $254,#190
   443          LDO $253,$254,0
   444          ADDU $254,$254,8
   445          POP 1,0
   446          .data ! mmixal:= 8H LOC 9B