https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99016
Bug ID: 99016
Summary: Internal compiler error from decltype of binary
operator when one operand is a prvalue function call
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: david at doublewise dot net
Target Milestone: ---
The following valid translation unit
```
struct integer {};
integer f();
int operator+(integer, integer);
using max_type = decltype(f() + f());
```
Causes gcc to crash with
```
<source>:7:35: internal compiler error: in build_over_call, at cp/call.c:9244
7 | using max_type = decltype(f() + f());
| ^
0x1ce6f09 internal_error(char const*, ...)
???:0
0x6b6f43 fancy_abort(char const*, int, char const*)
???:0
0x6df89c build_new_method_call(tree_node*, tree_node*, vec<tree_node*, va_gc,
vl_embed>**, tree_node*, int, tree_node**, int)
???:0
0x6e1000 build_special_member_call(tree_node*, tree_node*, vec<tree_node*,
va_gc, vl_embed>**, tree_node*, int, int)
???:0
0x6e2760 build_new_op(op_location_t const&, tree_code, int, tree_node*,
tree_node*, tree_node*, tree_node**, int)
???:0
0x9c121d build_x_binary_op(op_location_t const&, tree_code, tree_node*,
tree_code, tree_node*, tree_code, tree_node**, int)
???:0
0x8de23d c_parse_file()
???:0
0xa5b7c2 c_common_parse_file()
???:0
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
Compiler returned: 1
```
This worked in gcc 10.2. See it live: https://godbolt.org/z/oxj437
