https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109887
Bug ID: 109887
Summary: Different mangled name for template specialization for
clang and gcc
Product: gcc
Version: 12.3.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: yedeng.yd at linux dot alibaba.com
Target Milestone: ---
(This is a duplication of https://github.com/llvm/llvm-project/issues/62765
since I don't know which one is worse)
Reproducer:
```
#include <type_traits>
namespace llvm {
class StringRef {
public:
StringRef(const char*);
};
template <typename T> class Optional {};
}
namespace n {
struct S {
template <class T>
std::enable_if_t<std::is_integral<T>::value, llvm::Optional<T>>
get(llvm::StringRef) const {
return {};
}
};
template <>
llvm::Optional<bool>
S::get<bool>(llvm::StringRef) const;
}
void use() {
n::S().get<bool>("hello");
}
```
For the specialization `S::get<bool>(llvm::StringRef)`, gcc will mangle it as:
```
_ZNK1n1S3getIbEENSt9enable_ifIXsrSt11is_integralIT_E5valueEN4llvm8OptionalIS4_EEE4typeENS6_9StringRefE
```
and clang will mangle it as:
```
_ZNK1n1S3getIbEENSt9enable_ifIXsr3std11is_integralIT_EE5valueEN4llvm8OptionalIS3_EEE4typeENS4_9StringRefE
```
Also the c++filt can only recognize the name mangled by gcc. And the
llvm-cxxfilt can only recognize the name mangled by clang.
So I am not sure if this is bug really or this is by design. But I think clang
and gcc are trying to make ABI compatible.
