[glib/glib-2-64: 3/4] Silence clang errors about -Wformat-nonliteral due to missing intermediate attributes

[Emmanuele Bassi <ebassi src gnome org>]

commit 693013bba51e156b45a952f730b8009c8712fce8
Author: Martin Storsjö <martin martin st>
Date:   Sun Apr 5 00:06:37 2020 +0300

    Silence clang errors about -Wformat-nonliteral due to missing intermediate attributes
    
    By default, meson builds glib with -Werror=format=2, which
    implies -Werror=format-nonliteral. With these flags, clang errors
    out on e.g. the g_message_win32_error function, due to "format
    string is not a string literal". This function takes a format
    string, and passes the va_list of the arguments onwards to
    g_strdup_vprintf, which is annotated with printf attributes.
    
    When passing a string+va_list to another function, GCC doesn't warn
    with -Wformat-nonliteral. Clang however does warn, unless the
    functions themselves (g_message_win32_error and set_error) are decorated
    with similar printf attributes (to force the same checks upon the
    caller) - see
    https://clang.llvm.org/docs/AttributeReference.html#format
    for reference.
    
    Adding these attributes revealed one existing mismatched format string
    (fixed in the preceding commit).

 gio/gregistrysettingsbackend.c | 2 +-
 gmodule/gmodule-win32.c        | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gio/gregistrysettingsbackend.c b/gio/gregistrysettingsbackend.c
index 9f9d718574..b0e295a043 100644
--- a/gio/gregistrysettingsbackend.c
+++ b/gio/gregistrysettingsbackend.c
@@ -201,7 +201,7 @@ trace (const char *format,
  * equivalent function for g_warning because none of the registry errors can
  * result from programmer error (Microsoft programmers don't count), instead
  * they will mostly occur from people messing with the registry by hand. */
-static void
+static void G_GNUC_PRINTF (2, 3)
 g_message_win32_error (DWORD        result_code,
                        const gchar *format,
                       ...)
diff --git a/gmodule/gmodule-win32.c b/gmodule/gmodule-win32.c
index 5057d256ec..fef4d893de 100644
--- a/gmodule/gmodule-win32.c
+++ b/gmodule/gmodule-win32.c
@@ -39,7 +39,7 @@
 #include <sys/cygwin.h>
 #endif
 
-static void
+static void G_GNUC_PRINTF (1, 2)
 set_error (const gchar *format,
           ...)
 {