[Bug inline-asm/98991] ICE: Max. number of generated reload insns per insn is achieved (90)

["zhan3299 at purdue dot edu" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98991

--- Comment #3 from zhan3299 at purdue dot edu ---
(In reply to Martin Liška from comment #1)
> Is it a valid or invalid code, please?

Hi, sorry for the confusion. I used a simple delta debugging to reduce the
test-case, and it seems very confused.

Currently, I use C-Reduce to get a simple test-case:


--- poc.cc starts ---
void a() {
  float b;
  asm("" : "=rmf"(b) : "0"(0));
  &b;
}
--- poc.cc ends ---


run 'gcc poc.cc -fpermissive' and we can get the same ICE.


--- error trace starts ---
during RTL pass: reload
poc.cc: In function 'void a()':
poc.cc:5:1: internal compiler error: maximum number of generated reload insns
per insn achieved (90)
    5 | }
      | ^
0x20cb324 lra_constraints(bool)
        ../../gcc/gcc/lra-constraints.c:4951
0x20ab2c8 lra(_IO_FILE*)
        ../../gcc/gcc/lra.c:2440
0x1ff80de do_reload()
        ../../gcc/gcc/ira.c:5523
0x1ff80de (anonymous namespace)::pass_reload::execute(function*)
        ../../gcc/gcc/ira.c:5709
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
--- error trace ends ---


I test it with gcc 10.2.0, but it seems my native 7.5.0 also failed.