Meson: Compensate for the lack of msvc_recommended_pragmas.h

fanc999-1 · fanc999-1 · commit 063a96f64843 · 2022-05-23T18:56:50.000+08:00
libsigc++ does not depend on GLib, so msvc_recommended_pragmas.h may not be
available.  If it isn't, disable warning C4244 to compensate for it.
diff --git a/meson.build b/meson.build
@@ -184,7 +184,16 @@ add_project_arguments(warning_flags, language: 'cpp')
 # MSVC: Ignore warnings that aren't really harmful, but make those
 #       that should not be overlooked stand out.
 if is_msvc
-  foreach wd : ['/FImsvc_recommended_pragmas.h', '/EHsc', '/wd4267']
+  # Turn off harmless warnings but make potentially dangerous ones glaring,
+  # distributed with GLib, if available
+  use_recommended_pragmas =  cpp_compiler.get_supported_arguments('/FImsvc_recommended_pragmas.h')
+  if use_recommended_pragmas.length() > 0
+    add_project_arguments(use_recommended_pragmas, language: 'cpp')
+  else
+    disabled_warning = cpp_compiler.get_supported_arguments(['/wd4244'])
+    add_project_arguments(disabled_warning, language: 'cpp')
+  endif
+  foreach wd : ['/EHsc', '/wd4267']
     disabled_warning = cpp_compiler.get_supported_arguments(wd)
     add_project_arguments(disabled_warning, language: 'cpp')
   endforeach
