[PATCH 1/2] glibcompat: Provide implementation for G_GNUC_NO_INLINE

[Michal Privoznik]

Currently, we require glib-2.56.0 at minimum (because of RHEL-8)
but we use G_GNUC_NO_INLINE which was introduced in 2.58.0. While
we provide an implementation for older versions, where the macro
does not exists, it's a bit more tricky than that. Since we
define GLIB_VERSION_MAX_ALLOWED we would get a compile time error
when trying to use something too new, except for G_GNUC_NO_INLINE
which was intentionally not marked as
GLIB_AVAILABLE_MACRO_IN_2_58. But this is about to change with
glib-2.73.2 (which contains commit [1]).

At the same time, we can't just bump glib and thus we have to
provide an alternative implementation without the version
annotation.

1: https://gitlab.gnome.org/GNOME/glib/-/commit/a6f8fe071e44b0145619c21f3bfbc90c56ab805e
Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/internal.h        | 12 ------------
 src/util/glibcompat.h |  9 +++++++++
 2 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/src/internal.h b/src/internal.h
index 4cfb022b41..1e8e2908bf 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -109,18 +109,6 @@
 # endif
 #endif
 
-/**
- * G_GNUC_NO_INLINE:
- *
- * Force compiler not to inline a method. Should be used if
- * the method need to be overridable by test mocks.
- *
- * TODO: Remove after upgrading to GLib >= 2.58
- */
-#ifndef G_GNUC_NO_INLINE
-# define G_GNUC_NO_INLINE __attribute__((__noinline__))
-#endif
-
 /**
  * ATTRIBUTE_PACKED
  *
diff --git a/src/util/glibcompat.h b/src/util/glibcompat.h
index 1f3a6f728f..e3a8b9f6b3 100644
--- a/src/util/glibcompat.h
+++ b/src/util/glibcompat.h
@@ -94,3 +94,12 @@ char *vir_g_strdup_vprintf(const char *msg, va_list args)
 #define g_fsync vir_g_fsync
 
 void vir_g_source_unref(GSource *src, GMainContext *ctx);
+
+/* Intentionally redefine macro so that it's not marked as available in 2.58
+ * and newer. Drop when bumping to 2.58 or newer. */
+#undef G_GNUC_NO_INLINE
+#if g_macro__has_attribute(__noinline__)
+# define G_GNUC_NO_INLINE __attribute__ ((__noinline__))
+#else
+# define G_GNUC_NO_INLINE
+#endif
-- 
2.35.1