From 59c1c9cc9edeaaabbb5505c50860cef3481c57a0 Mon Sep 17 00:00:00 2001
From: Danny Robson <danny@nerdcruft.net>
Date: Mon, 19 Apr 2021 16:47:22 +1000
Subject: [PATCH] geom/ops: workaround ICE using `requires` for `distance`

clang requires `A<S,T>` for the `enable_if` condition, and this provokes
an ICE under GCC. A `requires` clause works identically and satisfies
both compilers.
---
 geom/ops.hpp | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/geom/ops.hpp b/geom/ops.hpp
index ee21a308..7f1eed6d 100644
--- a/geom/ops.hpp
+++ b/geom/ops.hpp
@@ -55,12 +55,12 @@ namespace cruft::geom {
         size_t S,
         typename T,
         template <size_t,typename> class A,
-        template <size_t,typename> class B,
-        typename = std::enable_if_t<
-            !std::is_same_v<cruft::point<S,T>, A<S,T>> &&
-            !std::is_same_v<cruft::point<S,T>, B<S,T>>
-        >
+        template <size_t,typename> class B
     >
+    requires (
+        !std::is_same_v<cruft::point<S,T>, A<S,T>> &&
+        !std::is_same_v<cruft::point<S,T>, B<S,T>>
+    )
     T
     distance (A<S,T>, B<S,T>);