https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105045
Bug ID: 105045
Summary: [modules] Can't deduce defaulted template parameter
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Keywords: rejects-valid
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: johelegp at gmail dot com
Target Milestone: ---
See https://godbolt.org/z/3WMd4T48h.
`mod.cpp`:
```C++
export module mod;
export template<int T=0, class U> void f(U) { }
```
`test.cpp`:
```C++
import mod;
int main() { f(0); }
```
Output:
```
test.cpp: In function 'int main()':
test.cpp:2:15: error: no matching function for call to 'f(int)'
2 | int main() { f(0); }
| ~^~~
In module mod, imported at /app/test.cpp:1:
mod.cpp:2:40: note: candidate: 'template<int T, class U> void f@mod(U)'
2 | export template<int T=0, class U> void f(U) { }
| ^
mod.cpp:2:40: note: template argument deduction/substitution failed:
test.cpp:2:15: note: couldn't deduce template parameter 'T'
2 | int main() { f(0); }
| ~^~~
```
