[PATCH] tst-unique4.cc: Explicitly instantiate S<N>::i

[Sam James]

"H.J. Lu" <hjl.tools@gmail.com> writes:

> Explicitly instantiate S<N>::i to silence Clang error:
>
> tst-unique4.cc:8:11: error: instantiation of variable 'S<1>::i' required here, but no definition is available [-Werror,-Wundefined-var-template]
>     8 |     S<1>::i, S<2>::i, S<3>::i, S<4>::i, S<5>::i, S<6>::i, S<7>::i, S<8>::i,
>       |           ^
> ./tst-unique4.h:5:14: note: forward declaration of template entity is here
>     5 |   static int i;
>       |              ^
> tst-unique4.cc:8:11: note: add an explicit instantiation declaration to suppress this warning if 'S<1>::i' is explicitly instantiated in another translation unit
>     8 |     S<1>::i, S<2>::i, S<3>::i, S<4>::i, S<5>::i, S<6>::i, S<7>::i, S<8>::i,
>       |           ^
>

Please try:

--- a/elf/tst-unique4.h
+++ b/elf/tst-unique4.h
@@ -2,6 +2,6 @@
 template<int N>
 struct S
 {
-  static int i;
+  inline static int i;
   static const int j;
 };

with C++17.

> Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
> ---
>  elf/tst-unique4.cc | 49 ++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 49 insertions(+)
>
> diff --git a/elf/tst-unique4.cc b/elf/tst-unique4.cc
> index 575c70d3a1..f38d7c094f 100644
> --- a/elf/tst-unique4.cc
> +++ b/elf/tst-unique4.cc
> @@ -3,6 +3,55 @@
>  
>  #include <cstdio>
>  
> +template<>
> +int S<1>::i = 1;
> +template<>
> +int S<2>::i = 2;
> +template<>
> +int S<3>::i = 3;
> +template<>
> +int S<4>::i = 4;
> +template<>
> +int S<5>::i = 5;
> +template<>
> +int S<6>::i = 6;
> +template<>
> +int S<7>::i = 7;
> +template<>
> +int S<8>::i = 8;
> +template<>
> +int S<9>::i = 9;
> +template<>
> +int S<10>::i = 10;
> +template<>
> +int S<11>::i = 11;
> +template<>
> +int S<12>::i = 12;
> +template<>
> +int S<13>::i = 13;
> +template<>
> +int S<14>::i = 14;
> +template<>
> +int S<15>::i = 15;
> +template<>
> +int S<16>::i = 16;
> +template<>
> +int S<17>::i = 17;
> +template<>
> +int S<18>::i = 18;
> +template<>
> +int S<19>::i = 19;
> +template<>
> +int S<20>::i = 20;
> +template<>
> +int S<21>::i = 21;
> +template<>
> +int S<22>::i = 22;
> +template<>
> +int S<23>::i = 23;
> +template<>
> +int S<24>::i = 24;
> +
>  static int a[24] =
>    {
>      S<1>::i, S<2>::i, S<3>::i, S<4>::i, S<5>::i, S<6>::i, S<7>::i, S<8>::i,