[sysprof] build: avoid some compile checks on clang 12

[Christian Hergert <chergert src gnome org>]

commit 621fd70e81a3c75d03a236abc952858303c73163
Author: Christian Hergert <chergert redhat com>
Date:   Mon Nov 16 14:04:38 2020 -0800

    build: avoid some compile checks on clang 12

 meson.build | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index 590b98a..8966a56 100644
--- a/meson.build
+++ b/meson.build
@@ -114,7 +114,6 @@ test_c_args = [
   ['-Werror=format-security', '-Werror=format=2' ],
   '-Werror=empty-body',
   '-Werror=implicit-function-declaration',
-  '-Werror=incompatible-pointer-types',
   '-Werror=pointer-arith',
   '-Werror=init-self',
   '-Werror=int-conversion',
@@ -127,6 +126,14 @@ test_c_args = [
   '-Werror=strict-prototypes',
   '-Werror=undef',
 ]
+
+# Until GLib is fixed with regards to volatile type registration
+if cc.get_id() == 'clang'
+  test_c_args += ['-Wno-incompatible-pointer-types']
+else
+  test_c_args += ['-Werror=incompatible-pointer-types']
+endif
+
 if get_option('buildtype') != 'plain'
   test_c_args += '-fstack-protector-strong'
 endif