https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121094
Bug ID: 121094
Summary: ICE on `co_await (obj->*func)(args...)`
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: dprokoptsev at gmail dot com
Target Milestone: ---
Created attachment 61869
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=61869&action=edit
Preprocessed source
Current g++ (built from commit d8680bac95c) ICEs when trying to build a test
suite for a coroutine library:
/home/dmitryp/src/corral/test/../corral/Nursery.h:795:43: internal compiler
error: in gimple_add_tmp_var, at gimplify.cc:837
795 | co_await (obj->*c)(std::move(a)...);
| ~~~~~~~~~^~~~~~~~~~~~~~~~~
0x358ccca internal_error(char const*, ...)
../../gcc/diagnostic-global-context.cc:517
0x354a6bf fancy_abort(char const*, int, char const*)
../../gcc/diagnostic.cc:1818
0x15f7b72 gimple_add_tmp_var(tree_node*)
../../gcc/gimplify.cc:837
0x1613575 gimplify_target_expr
../../gcc/gimplify.cc:8368
0x16499b8 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
../../gcc/gimplify.cc:20192
0x164ac67 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
../../gcc/gimplify.cc:20550
0x1648723 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
../../gcc/gimplify.cc:19910
0x164ac67 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
../../gcc/gimplify.cc:20550
0x1648723 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
../../gcc/gimplify.cc:19910
0x160f20f gimplify_modify_expr
../../gcc/gimplify.cc:7337
0x1647e4d gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
../../gcc/gimplify.cc:19789
0x1613a59 gimplify_stmt(tree_node**, gimple**)
../../gcc/gimplify.cc:8461
0x160a029 gimplify_cond_expr
../../gcc/gimplify.cc:5658
0x1647cc9 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
../../gcc/gimplify.cc:19743
0x1613a59 gimplify_stmt(tree_node**, gimple**)
../../gcc/gimplify.cc:8461
0x1609205 gimplify_cond_expr
../../gcc/gimplify.cc:5536
0x1647cc9 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
../../gcc/gimplify.cc:19743
0xd71e3b gimplify_to_rvalue
../../gcc/cp/cp-gimplify.cc:556
0xd72de3 cp_gimplify_expr(tree_node**, gimple**, gimple**)
../../gcc/cp/cp-gimplify.cc:796
0x1647a93 gimplify_expr(tree_node**, gimple**, gimple**, bool (*)(tree_node*),
int)
../../gcc/gimplify.cc:19695
FWIW, splitting the expression to `auto x = (obj->*c)(std::move(a)...);
co_await std::move(x)` resolves the issue.
Also this used to work on gcc-14, and is apparently broken in gcc-15 and
gcc-16.
See the attached preprocessed source; I was not able to come up with a minimal
repro so far (but will try further).
