$ gdb --args wasmtime -g ./test.wasm
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Reading symbols from wasmtime...
(gdb) b test.cpp:7
No source file named test.cpp.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (test.cpp:7) pending.
(gdb) r
Starting program: /home/x/dev/tools/wasmtime -g ./test.wasm
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7ffff7a14640 (LWP 85266)]
[New Thread 0x7ffff7813640 (LWP 85267)]
[New Thread 0x7ffff7612640 (LWP 85268)]
[New Thread 0x7ffff740e640 (LWP 85269)]
[New Thread 0x7ffff720a640 (LWP 85270)]
[New Thread 0x7ffff7006640 (LWP 85271)]
[New Thread 0x7ffff6e02640 (LWP 85272)]
[New Thread 0x7ffff6bfe640 (LWP 85273)]
[New Thread 0x7ffff69fa640 (LWP 85274)]
[New Thread 0x7ffff67f6640 (LWP 85275)]
[New Thread 0x7ffff65f2640 (LWP 85276)]
[New Thread 0x7ffff63ee640 (LWP 85277)]
[New Thread 0x7ffff61ea640 (LWP 85278)]
warning: Loadable section ".eh_frame" outside of ELF segments
  in <in-memory>
warning: Loadable section ".wasmtime.addrmap" outside of ELF segments
  in <in-memory>
warning: Loadable section ".wasmtime.traps" outside of ELF segments
  in <in-memory>
warning: Loadable section ".rodata.wasm" outside of ELF segments
  in <in-memory>
warning: Loadable section ".wasmtime.info" outside of ELF segments
  in <in-memory>

Thread 1 "wasmtime" hit Breakpoint 1, Thing::Thing (this=..., i=5) at ./test.cpp:8
8	      m_i = i;
(gdb) p __vmctx->set()
gdbtypes.c:2880: internal-error: type* check_typedef(type*): Assertion `type' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
----- Backtrace -----
0x55bb3b31f8d1 gdb_internal_backtrace_1
	/home/x/dev/binutils-gdb/gdb/bt-utils.c:121
0x55bb3b31f8d1 _Z22gdb_internal_backtracev
	/home/x/dev/binutils-gdb/gdb/bt-utils.c:164
0x55bb3b6c17dc internal_vproblem
	/home/x/dev/binutils-gdb/gdb/utils.c:393
0x55bb3b6c1a70 _Z15internal_verrorPKciS0_P13__va_list_tag
	/home/x/dev/binutils-gdb/gdb/utils.c:470
0x55bb3b7e36d4 _Z14internal_errorPKciS0_z
	/home/x/dev/binutils-gdb/gdbsupport/errors.cc:55
0x55bb3b4626e5 _Z13check_typedefP4type
	/home/x/dev/binutils-gdb/gdb/gdbtypes.c:2880
0x55bb3b398c51 cp_lookup_bare_symbol
	/home/x/dev/binutils-gdb/gdb/cp-namespace.c:223
0x55bb3b3997ca lookup_namespace_scope
	/home/x/dev/binutils-gdb/gdb/cp-namespace.c:719
0x55bb3b39985f _Z25cp_lookup_symbol_nonlocalPK13language_defnPKcPK5block15domain_enum_tag
	/home/x/dev/binutils-gdb/gdb/cp-namespace.c:754
0x55bb3b62a446 lookup_symbol_aux
	/home/x/dev/binutils-gdb/gdb/symtab.c:2125
0x55bb3b62a5a3 _Z25lookup_symbol_in_languagePKcPK5block15domain_enum_tag8languageP20field_of_this_result
	/home/x/dev/binutils-gdb/gdb/symtab.c:1920
0x55bb3b32a68f classify_name
	/home/x/dev/binutils-gdb/gdb/c-exp.y:3069
0x55bb3b32c9a7 c_yylex
	/home/x/dev/binutils-gdb/gdb/c-exp.y:3277
0x55bb3b32d409 _Z9c_yyparsev
	/home/x/dev/binutils-gdb/gdb/c-exp.c.tmp:2037
0x55bb3b335a12 _Z7c_parseP12parser_state
	/home/x/dev/binutils-gdb/gdb/c-exp.y:3443
0x55bb3b54c9ab parse_exp_in_context
	/home/x/dev/binutils-gdb/gdb/parse.c:510
0x55bb3b54cd0a _Z16parse_expressionPKcP23innermost_block_trackerb
	/home/x/dev/binutils-gdb/gdb/parse.c:546
0x55bb3b551563 process_print_command_args
	/home/x/dev/binutils-gdb/gdb/printcmd.c:1311
0x55bb3b551abf print_command_1
	/home/x/dev/binutils-gdb/gdb/printcmd.c:1325
0x55bb3b357664 _Z8cmd_funcP16cmd_list_elementPKci
	cli/cli-decode.c:2459
0x55bb3b669020 _Z15execute_commandPKci
	/home/x/dev/binutils-gdb/gdb/top.c:670
0x55bb3b42a904 _Z15command_handlerPKc
	/home/x/dev/binutils-gdb/gdb/event-top.c:597
0x55bb3b42ac90 _Z20command_line_handlerOSt10unique_ptrIcN3gdb13xfree_deleterIcEEE
	/home/x/dev/binutils-gdb/gdb/event-top.c:782
0x55bb3b42b3f1 gdb_rl_callback_handler
	/home/x/dev/binutils-gdb/gdb/event-top.c:229
0x55bb3b7065b7 rl_callback_read_char
	/home/x/dev/binutils-gdb/readline/readline/callback.c:281
0x55bb3b429a85 gdb_rl_callback_read_char_wrapper_noexcept
	/home/x/dev/binutils-gdb/gdb/event-top.c:187
0x55bb3b42b2a4 gdb_rl_callback_read_char_wrapper
	/home/x/dev/binutils-gdb/gdb/event-top.c:204
0x55bb3b429667 _Z19stdin_event_handleriPv
	/home/x/dev/binutils-gdb/gdb/event-top.c:524
0x55bb3b7e3f65 gdb_wait_for_event
	/home/x/dev/binutils-gdb/gdbsupport/event-loop.cc:701
0x55bb3b7e420c gdb_wait_for_event
	/home/x/dev/binutils-gdb/gdbsupport/event-loop.cc:597
0x55bb3b7e420c _Z16gdb_do_one_eventv
	/home/x/dev/binutils-gdb/gdbsupport/event-loop.cc:237
0x55bb3b4f46f4 start_event_loop
	/home/x/dev/binutils-gdb/gdb/main.c:421
0x55bb3b4f46f4 captured_command_loop
	/home/x/dev/binutils-gdb/gdb/main.c:481
0x55bb3b4f6384 captured_main
	/home/x/dev/binutils-gdb/gdb/main.c:1348
0x55bb3b4f6384 _Z8gdb_mainP18captured_main_args
	/home/x/dev/binutils-gdb/gdb/main.c:1363
0x55bb3b2873ef main
	/home/x/dev/binutils-gdb/gdb/gdb.c:32
---------------------
gdbtypes.c:2880: internal-error: type* check_typedef(type*): Assertion `type' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.