[Bug c++/98718] [modules] use of partitions causes ICE in write_macro_maps

[nathan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98718

--- Comment #2 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
reduced testcase:

// b_a.ii
module ;

# 4 "inc_a" 1
#define _GLIBCXX_VISIBILITY(V) __attribute__ ((__visibility__ (#V)))

namespace std _GLIBCXX_VISIBILITY(default)
{

}
# 11 "" 2

export  module  hello:format;

// b_b.ii
module ;

# 4 "inc_b" 1
#define _GLIBCXX_VISIBILITY(V) __attribute__ ((__visibility__ (#V)))
#define _GLIBCXX_BEGIN_NAMESPACE_VERSION 
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
}
# 11 "" 2

export  module  hello;
export  import  :format;
zathras:210>./cc1plus -std=c++20 -fmodules-ts -quiet -fpreprocessed
-fdirectives-only b_a.ii && ./cc1plus -std=c++20 -fmodules-ts -quiet
-fpreprocessed -fdirectives-only b_b.ii
b_b.ii:12:9: internal compiler error: in write_macro_maps, at
cp/module.cc:16154
   12 | export  module  hello;
      |         ^~~~~~
0xce1ab0 module_state::write_macro_maps(elf_out*, location_map_info&,
module_state_config*, unsigned int*)
        ../../../src/gcc/cp/module.cc:16154
0xce662b module_state::write(elf_out*, cpp_reader*)
        ../../../src/gcc/cp/module.cc:17771
0xcec7d8 finish_module_processing(cpp_reader*)
        ../../../src/gcc/cp/module.cc:19860