Sorry, this is with gcc-9.0.1-0.3.fc30.ppc64le.

It turns out that cpp-debuginfo has the debugging information for cc1.  With that, I get:

#0  0x00000000109627ac in lra_constraints (first_p=<optimized out>) a
   t ../../gcc/lra-constraints.c:4763
#1  0x0000000010f131a4 in lra (f=<optimized out>) at ../../gcc/lra.c:2461
#2  0x0000000010ef1f58 in do_reload () at ../../gcc/ira.c:5516
#3  (anonymous namespace)::pass_reload::execute (this=<optimized out>) at ../../gcc/ira.c:5700
#4  0x000000001098bdf4 in execute_one_pass (pass=0x11884570) at ../../gc
   c/passes.c:2483
#5  execute_pass_list_1 (pass=0x11884570) at ../../gcc/passes.c:2569
#6  0x000000001098c5c4 in execute_pass_list_1 (pass=0x11883430) at ../..
   /gcc/passes.c:2570
#7  0x0000000010f3f068 in execute_pass_list (fn=<optimized out>, 
pass=<optimized out>) at ../../gcc/passes.c:2580
#8  0x0000000010e300b4 in cgraph_node::expand (this=this@entry
=0x7ffff5a64218) at ../../gcc/context.h:48
#9  0x0000000010e2ee64 in expand_all_functions () at ../../gcc/cgraphunit.c:2333
#10 symbol_table::compile (this=this@entry=0x7ffff5a80000) at ../../gcc/cgraphunit.c:2684
#11 0x0000000010e2deac in symbol_table::finalize_compilation_unit (this=
    0x7ffff5a80000) at ../../gcc/cgraphunit.c:2862
#12 0x0000000010f63a10 in compile_file () at ../../gcc/toplev.c:482
#13 0x0000000010730e58 in do_compile () at ../../gcc/toplev.c:2177
#14 toplev::main (this=0x7fffffffef56, argc=<optimized out>, argv=<optimized
     out>) at ../../gcc/toplev.c:2312
#15 0x0000000010732ff4 in main (argc=<optimized out>, argv=
    0x7ffffffff378) at ../../gcc/main.c:39

Looks like we never exit the outer for loop here in gcc/lra.c:lra:

   │2457          for (;;)                                                                                            │
   │2458            {                                                                                                 │
   │2459              for (;;)                                                                                        │
   │2460               {                                                                                              │
   │2461                 bool reloads_p = lra_constraints (lra_constraint_iter == 0);                                 │
   │2462                 /* Constraint transformations may result in that eliminable                                  │
   │2463                    hard regs become uneliminable and pseudos which use them                                  │
   │2464                    should be spilled.         It is better to do it before pseudo                            │
   │2465                    assignments.                                                                              │
   │2466                                                                                                              │
   │2467                    For example, rs6000 can make                                                              │
   │2468                    RS6000_PIC_OFFSET_TABLE_REGNUM uneliminable if we started                                 │
   │2469                    to use a constant pool.  */                                                               │
   │2470                 lra_eliminate (false, false);                                                                │

This bug appears to have been reported against 'rawhide' during the Fedora 31 development cycle.
Changing version to '31'.

This bug appears to have been reported against 'rawhide' during the Fedora 31 development cycle.
Changing version to 31.

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