[glib/wip/3v1n0/g_str_has_optimization] gstrfuncs: workaround build failure with some compilers

[Marco Trevisan <marcotrevi src gnome org>]

commit 61f36ec97bbec0e79b437f067c45236427efca42
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Thu Oct 13 02:18:00 2022 +0200

    gstrfuncs: workaround build failure with some compilers
    
    For some reason we may get warnings about using NULL parameters, while
    this is impossible

 glib/gstrfuncs.h      | 8 ++++----
 glib/tests/strfuncs.c | 8 ++++++++
 2 files changed, 12 insertions(+), 4 deletions(-)
---
diff --git a/glib/gstrfuncs.h b/glib/gstrfuncs.h
index 19eb291bef..f8c09f335a 100644
--- a/glib/gstrfuncs.h
+++ b/glib/gstrfuncs.h
@@ -151,8 +151,8 @@ gboolean g_str_has_prefix (const gchar *str,
   (((STR) != NULL && (PREFIX) != NULL && __builtin_constant_p ((PREFIX))) ? \
     G_GNUC_EXTENSION ({                                                     \
       G_STATIC_ASSERT (sizeof (PREFIX[0]) == sizeof (char));                \
-      const char *const __str = ((STR));                                    \
-      const char *const __prefix = ((PREFIX));                              \
+      const char *const __str = ((STR) + !(STR));                           \
+      const char *const __prefix = ((PREFIX) + !(PREFIX));                  \
       const size_t __str_len = strlen (__str);                              \
       const size_t __prefix_len = sizeof ((PREFIX)) - 1;                    \
       (__str_len >= __prefix_len) ?                                         \
@@ -165,8 +165,8 @@ gboolean g_str_has_prefix (const gchar *str,
   (((STR) != NULL && (SUFFIX) != NULL && __builtin_constant_p ((SUFFIX))) ? \
     G_GNUC_EXTENSION ({                                                     \
       G_STATIC_ASSERT (sizeof (SUFFIX[0]) == sizeof (char));                \
-      const char *const __str = ((STR));                                    \
-      const char *const __suffix = ((SUFFIX));                              \
+      const char *const __str = ((STR) + !(STR));                           \
+      const char *const __suffix = ((SUFFIX) + !(SUFFIX));                  \
       const size_t __str_len = strlen (__str);                              \
       const size_t __suffix_len = sizeof ((SUFFIX)) - 1;                    \
       (__str_len >= __suffix_len) ?                                         \
diff --git a/glib/tests/strfuncs.c b/glib/tests/strfuncs.c
index e7d3e108e7..fdc2b3a54a 100644
--- a/glib/tests/strfuncs.c
+++ b/glib/tests/strfuncs.c
@@ -1285,7 +1285,15 @@ test_has_prefix_macro (void)
   rand_str[7] = 'A';
   rand_str[8] = 'A';
   rand_str[9] = '\0';
+
+#if G_GNUC_CHECK_VERSION (2, 0)
+  _Pragma ("GCC diagnostic push")
+  _Pragma ("GCC diagnostic ignored \"-Waddress\"")
+  g_assert_true (g_str_has_prefix (rand_str, rand_prefix));
+  _Pragma ("GCC diagnostic pop")
+#else
   g_assert_true (g_str_has_prefix (rand_str, rand_prefix));
+#endif
 
   res = g_str_has_prefix ("foo", "bar");
   g_assert_cmpint (res, ==, FALSE);