On 2016.03.25 at 17:29 -0400, Jason Merrill wrote:
> 70353 is a problem with the function-local static declaration of __func__.
> Normally constexpr functions can't have local statics, so this is only an
> issue with __func__. Meanwhile, core issue 1962 looks like it's going to be
> resolved by changing __func__ et al to be prvalue constants of type const
> char * rather than static local array variables, so implementing that
> proposed resolution also resolves this issue, as well as 62466 which
> complains about the strings not being merged between translation units.
> This patch proceeds from Martin's work last year.
>
> Tested x86_64-pc-linux-gnu, applying to trunk.
It breaks building Firefox:
trippels@gcc2-power8 places % cat nsNavHistory.ii
struct A {
template <int N> A(const char (&)[N]);
};
void fn1() { A(__func__); }
trippels@gcc2-power8 places % c++ -c nsNavHistory.ii
nsNavHistory.ii: In function ‘void fn1()’:
nsNavHistory.ii:4:24: error: no matching function for call to ‘A::A(const
char*&)’
void fn1() { A(__func__); }
^
nsNavHistory.ii:2:20: note: candidate: template<int N> A::A(const char (&)[N])
template <int N> A(const char (&)[N]);
^
nsNavHistory.ii:2:20: note: template argument deduction/substitution failed:
nsNavHistory.ii:4:24: note: mismatched types ‘const char [N]’ and ‘const
char*’
void fn1() { A(__func__); }
^
nsNavHistory.ii:1:8: note: candidate: constexpr A::A(const A&)
struct A {
^
nsNavHistory.ii:1:8: note: no known conversion for argument 1 from ‘const
char*’ to ‘const A&’
nsNavHistory.ii:1:8: note: candidate: constexpr A::A(A&&)
nsNavHistory.ii:1:8: note: no known conversion for argument 1 from ‘const
char*’ to ‘A&&’
So I'm not sure if your patch is really appropriate at this time.
Maybe waiting until next stage 1 would be better?
--
Markus
