cppinsights loses template<> in explicit function template specializations #200
Description
For the following code
template<typename U, typename ...T>
void f(U, T... rest)
{
if constexpr (sizeof...(rest) != 0)
f(rest...);
}
template<>
void f<int>(int) {}
int main()
{
f(0, 1);
}template<typename U, typename ...T>
void f(U, T... rest)
{
if constexpr (sizeof...(rest) != 0)
f(rest...);
}
/* First instantiated from: insights.cpp:13 */
#ifdef INSIGHTS_USE_TEMPLATE
template<>
void f<int, int>(int, int __rest1)
{
if constexpr(1 != 0) f(__rest1);
}
#endif
void f<int, >(int)
{
}
int main()
{
f(0, 1);
}Note that there is no template<> before the explicit specialization
void f<int, >(int)
{
}Maybe because explicit specializations look similar to ordinary function declarations in the AST:
TranslationUnitDecl
|-FunctionTemplateDecl <line:1:1, line:6:1> line:2:6 f
...
| `-FunctionDecl <line:2:1, line:6:1> line:2:6 used f 'void (int, int)'
| |-TemplateArgument type 'int'
| |-TemplateArgument pack
| | `-TemplateArgument type 'int'
...
|-FunctionDecl prev 0x5611456d1ff8 <line:8:1, line:9:19> col:6 used f 'void (int)'
| |-TemplateArgument type 'int'
| |-TemplateArgument pack
| |-ParmVarDecl <col:13> col:16 'int'
| `-CompoundStmt <col:18, col:19>
The f<int, int> instantiation is a child of the FunctionTemplateDecl, but the explicit specialization is not. It is a direct child of the TranslationUnitDecl.
However, an ordinary function declaration would not have the prev 0xXXX... part and TemplateArguments. void f(int) {} is turned into
|-FunctionDecl <line:11:1, col:14> col:6 f 'void (int)'
| |-ParmVarDecl <col:8> col:11 'int'
| `-CompoundStmt <col:13, col:14>