cmCMakePath: do not use std::filesystem::path with RH gcc-toolset-10

Fixes: #25458, #25453

1 files changed, 28 insertions, 0 deletions

diff --git a/Source/Checks/cm_cxx_filesystem.cxx b/Source/Checks/cm_cxx_filesystem.cxx
index 732f28f..c8df589 100644
--- a/Source/Checks/cm_cxx_filesystem.cxx
+++ b/Source/Checks/cm_cxx_filesystem.cxx
@@ -1,5 +1,8 @@
 
 #include <filesystem>
+#if defined(__GLIBCXX__)
+#  include <string_view>
+#endif
 
 int main()
 {
@@ -34,5 +37,30 @@ int main()
   p5.remove_filename();
 #endif
 
+#if defined(__GLIBCXX__)
+  // RH gcc-toolset-10 has a strange bug: it selects, in some circumstances,
+  // the wrong constructor which generate error in template instantiation.
+  class my_string_view : std::string_view
+  {
+  public:
+    my_string_view(const char* p)
+      : std::string_view(p)
+    {
+    }
+  };
+  class my_path
+  {
+  public:
+    my_path(std::filesystem::path path) {}
+
+    my_path(my_string_view path) {}
+  };
+
+  my_path p{ my_string_view{ "abc" } };
+  // here is the bug: the constructor taking std::filesystem::path as argument
+  // is selected, so the compiler try to build a std::filesystem::path instance
+  // from the my_string_view argument and fails to do so.
+#endif
+
   return 0;
 }