[Bug c++/102598] New: [modules] ICE in pp_string, at pretty-print.c

[johelegp at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102598

            Bug ID: 102598
           Summary: [modules] ICE in pp_string, at pretty-print.c
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: johelegp at gmail dot com
                CC: johelegp at gmail dot com
  Target Milestone: ---

See https://godbolt.org/z/3rGTTr6jE.

write.cpp:
```C++
export module write;
export void write(const auto &v) {}
```

main.cpp:
```C++
import write;
int main() { write(char{}); }
```

Compile commands:
```
gcc -Wall -Wextra -fmodules-ts -std=c++23 -c write.cpp
gcc -Wall -Wextra -fmodules-ts -std=c++23 -c main.cpp
```

Output:
```
In module write, imported at main.cpp:1:
in pp_string, at pretty-print.c:1827
0x2068f9d internal_error(char const*, ...)
        ???:0
0x973872 fancy_abort(char const*, int, char const*)
        ???:0
0x2086861 pp_format(pretty_printer*, text_info*)
        ???:0
0x2087d92 pp_verbatim(pretty_printer*, char const*, ...)
        ???:0
0x2067adf diagnostic_report_diagnostic(diagnostic_context*, diagnostic_info*)
        ???:0
0x2068720 warning_at(unsigned int, int, char const*, ...)
        ???:0
0xca067c do_warn_unused_parameter(tree_node*)
        ???:0
0xa3ba82 finish_function(bool)
        ???:0
0xb77dfb instantiate_decl(tree_node*, bool, bool)
        ???:0
0xb9b883 instantiate_pending_templates(int)
        ???:0
0xa50e3c c_parse_final_cleanups()
        ???:0
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://bugs.archlinux.org/> for instructions.
```