[Bug c/84240] New: Error in extract_constrain_insn, at recog.c:2246

[xvl5190 at psu dot edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84240

            Bug ID: 84240
           Summary: Error in extract_constrain_insn, at recog.c:2246
           Product: gcc
           Version: 5.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: xvl5190 at psu dot edu
  Target Milestone: ---

Building modified tests by turning on the optimizations. Get internal errors:

gcc -w -O1 asm-flag-6.c_0.1.c 
asm-flag-6.c_0.1.c: In function ‘TestP’:
asm-flag-6.c_0.1.c:5:2: error: unrecognizable insn:
  __asm__ ("addb $1, %1" : "=@ccnp"(r), "+r"(res)); if (r) return 1; } return
0; } char TestS () { char r, res = 1; /* sign bit set. 
  ^
(insn 13 12 16 3 (parallel [
            (set (reg:QI 0 ax [orig:96 r ] [96])
                (asm_operands:QI ("addb $1, %1") ("=@ccnp") 0 [
                        (reg:QI 1 dx [orig:97 res ] [97])
                    ]
                     [
                        (asm_input:QI ("1") asm-flag-6.c_0.1.c:5)
                    ]
                     [] asm-flag-6.c_0.1.c:5))
            (set (reg:QI 1 dx [orig:97 res ] [97])
                (asm_operands:QI ("addb $1, %1") ("=r") 1 [
                        (reg:QI 1 dx [orig:97 res ] [97])
                    ]
                     [
                        (asm_input:QI ("1") asm-flag-6.c_0.1.c:5)
                    ]
                     [] asm-flag-6.c_0.1.c:5))
            (clobber (reg:QI 18 fpsr))
            (clobber (reg:QI 17 flags))
        ]) asm-flag-6.c_0.1.c:5 -1
     (nil))
asm-flag-6.c_0.1.c:5:2: internal compiler error: in extract_constrain_insn, at
recog.c:2246
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