all: suppress wrong gcc-12 warning "-Wdangling-pointer"

gcc-12.0.1-0.8.fc36 is annoying with false positives.
It's related to g_error() and its `for(;;) ;`.

For example:

    ../src/libnm-glib-aux/nm-shared-utils.c: In function 'nm_utils_parse_inaddr_bin_full':
    ../src/libnm-glib-aux/nm-shared-utils.c:1145:26: error: dangling pointer to 'error' may be used [-Werror=dangling-pointer=]
     1145 |                     error->message);
          |                          ^~
    /usr/include/glib-2.0/glib/gmessages.h:343:32: note: in definition of macro 'g_error'
      343 |                                __VA_ARGS__);         \
          |                                ^~~~~~~~~~~
    ../src/libnm-glib-aux/nm-shared-utils.c:1133:31: note: 'error' declared here
     1133 |         gs_free_error GError *error = NULL;
          |                               ^~~~~
    /usr/include/glib-2.0/glib/gmessages.h:341:25: error: dangling pointer to 'addrbin' may be used [-Werror=dangling-pointer=]
      341 |                         g_log (G_LOG_DOMAIN,         \
          |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      342 |                                G_LOG_LEVEL_ERROR,    \
          |                                ~~~~~~~~~~~~~~~~~~~~~~~
      343 |                                __VA_ARGS__);         \
          |                                ~~~~~~~~~~~~
    ../src/libnm-glib-aux/nm-shared-utils.c:1141:13: note: in expansion of macro 'g_error'
     1141 |             g_error("unexpected assertion failure: could parse \"%s\" as %s, but not accepted by "
          |             ^~~~~~~
    ../src/libnm-glib-aux/nm-shared-utils.c:1112:14: note: 'addrbin' declared here
     1112 |     NMIPAddr addrbin;
          |              ^~~~~~~

I think the warning could potentially be useful and prevent real bugs.
So don't disable it altogether, but go through the effort to suppress it
at the places where it currently happens.

Note that NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER macro only expands
to suppressing the warning with __GNUC__ equal to 12. The purpose is to
only suppress the warning where we know we want to. Hopefully other gcc
versions don't have this problem.

I guess, we could also write a NM_COMPILER_WARNING() check in
"m4/compiler_options.m4", to disable the warning if we detect it. But
that seems too cumbersome.

11 files changed, 54 insertions, 8 deletions

diff --git a/src/core/platform/tests/test-common.c b/src/core/platform/tests/test-common.c
index 9053d35173..864c97dd10 100644
--- a/src/core/platform/tests/test-common.c
+++ b/src/core/platform/tests/test-common.c
@@ -241,6 +241,7 @@ _nmtstp_platform_ip_addresses_assert(const char        *filename,
         if ((IS_IPv4 ? force_exact_4 : force_exact_6) && nm_g_ptr_array_len(plat_addrs) > 0) {
             char sbuf[sizeof(_nm_utils_to_string_buffer)];
 
+            NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
             g_error("%s:%d: %u IPv%c addresses found on ifindex %d that should not be there (one "
                     "is %s)",
                     filename,
@@ -252,6 +253,7 @@ _nmtstp_platform_ip_addresses_assert(const char        *filename,
                                          NMP_OBJECT_TO_STRING_PUBLIC,
                                          sbuf,
                                          sizeof(sbuf)));
+            NM_PRAGMA_WARNING_REENABLE
         }
     }
 }
@@ -580,6 +582,7 @@ _nmtstp_assert_ip4_route_exists(const char *file,
     if (c != c_exists && c_exists != -1) {
         char sbuf[NM_UTILS_INET_ADDRSTRLEN];
 
+        NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
         g_error("[%s:%u] %s(): The ip4 route %s/%d metric %u tos %u shall exist %u times, but "
                 "platform has it %u times",
                 file,
@@ -591,6 +594,7 @@ _nmtstp_assert_ip4_route_exists(const char *file,
                 tos,
                 c_exists,
                 c);
+        NM_PRAGMA_WARNING_REENABLE
     }
 
     return r;
@@ -673,6 +677,7 @@ _nmtstp_assert_ip6_route_exists(const char            *file,
         char s_src[NM_UTILS_INET_ADDRSTRLEN];
         char s_network[NM_UTILS_INET_ADDRSTRLEN];
 
+        NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
         g_error("[%s:%u] %s(): The ip6 route %s/%d metric %u src %s/%d shall exist %u times, but "
                 "platform has it %u times",
                 file,
@@ -685,6 +690,7 @@ _nmtstp_assert_ip6_route_exists(const char            *file,
                 src_plen,
                 c_exists,
                 c);
+        NM_PRAGMA_WARNING_REENABLE
     }
 
     return r;
diff --git a/src/core/platform/tests/test-platform-general.c b/src/core/platform/tests/test-platform-general.c
index 9629326aa3..6d156d2a87 100644
--- a/src/core/platform/tests/test-platform-general.c
+++ b/src/core/platform/tests/test-platform-general.c
@@ -731,15 +731,17 @@ test_platform_ip_address_pretty_sort_cmp(gconstpointer test_data)
                                             &bin_len);
 
         if (bin_len != ELM_SIZE * N_ADDRESSES || memcmp(addresses, bin_arr, bin_len) != 0) {
-            char *addresses_str = nm_utils_bin2hexstr(addresses, ELM_SIZE * N_ADDRESSES, -1);
+            gs_free char *addresses_str = NULL;
 
+            NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
             g_error(">>> test_platform_ip_address_pretty_sort_cmp() will fail:\n"
                     ">>> addresses[%zu]: %s\n"
                     ">>> expected [%zu]: %s\n",
                     ELM_SIZE * N_ADDRESSES,
-                    addresses_str,
+                    (addresses_str = nm_utils_bin2hexstr(addresses, ELM_SIZE * N_ADDRESSES, -1)),
                     bin_len,
                     EXPECTED_BUFFER[TEST_DATA_I]);
+            NM_PRAGMA_WARNING_REENABLE
         }
 
         g_assert_cmpmem(addresses, ELM_SIZE * N_ADDRESSES, bin_arr, bin_len);
diff --git a/src/core/settings/plugins/ifcfg-rh/tests/test-ifcfg-rh.c b/src/core/settings/plugins/ifcfg-rh/tests/test-ifcfg-rh.c
index 7960ea2a9c..83e48b81b8 100644
--- a/src/core/settings/plugins/ifcfg-rh/tests/test-ifcfg-rh.c
+++ b/src/core/settings/plugins/ifcfg-rh/tests/test-ifcfg-rh.c
@@ -221,6 +221,7 @@ _assert_expected_content(NMConnection *connection, const char *filename, const c
             success = g_file_set_contents(expected, content_written, len_written, &error);
             nmtst_assert_success(success, error);
         } else {
+            NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
             g_error(
                 "The content of \"%s\" (%zu) differs from \"%s\" (%zu). Set "
                 "NMTST_IFCFG_RH_UPDATE_EXPECTED=yes (or NM_TEST_REGENERATE=1) to update the files "
@@ -231,6 +232,7 @@ _assert_expected_content(NMConnection *connection, const char *filename, const c
                 len_expectd,
                 content_written,
                 content_expectd);
+            NM_PRAGMA_WARNING_REENABLE
         }
     }
 }
diff --git a/src/core/settings/plugins/keyfile/tests/test-keyfile-settings.c b/src/core/settings/plugins/keyfile/tests/test-keyfile-settings.c
index b4c30df7d2..11a8e4169c 100644
--- a/src/core/settings/plugins/keyfile/tests/test-keyfile-settings.c
+++ b/src/core/settings/plugins/keyfile/tests/test-keyfile-settings.c
@@ -2635,8 +2635,11 @@ _escape_filename(gboolean with_extension, const char *filename, gboolean would_b
     g_assert(esc && esc[0]);
     g_assert(!strchr(esc, '/'));
 
-    if (nm_keyfile_utils_ignore_filename(esc, with_extension))
+    if (nm_keyfile_utils_ignore_filename(esc, with_extension)) {
+        NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
         g_error("Escaping filename \"%s\" yielded \"%s\", but this is ignored", filename, esc);
+        NM_PRAGMA_WARNING_REENABLE
+    }
 }
 
 static void
diff --git a/src/libnm-client-impl/tests/test-libnm.c b/src/libnm-client-impl/tests/test-libnm.c
index 0f600a4a01..d3265e9fb4 100644
--- a/src/libnm-client-impl/tests/test-libnm.c
+++ b/src/libnm-client-impl/tests/test-libnm.c
@@ -2327,13 +2327,14 @@ _do_read_vpn_details_impl1(const char              *file,
                 if (nm_streq(_expected[_i].key, _k))                                          \
                     break;                                                                    \
             }                                                                                 \
-            if (_i >= _expected_len)                                                          \
+            if (_i >= _expected_len) {                                                        \
                 g_error("%s:%d: hash '%s' contains unexpected data key '%s' with value '%s'", \
                         file,                                                                 \
                         line,                                                                 \
                         G_STRINGIFY(hash),                                                    \
                         _k,                                                                   \
                         _v);                                                                  \
+            }                                                                                 \
         }                                                                                     \
                                                                                               \
         for (_i = 0; _i < _expected_len; _i++) {                                              \
@@ -2342,7 +2343,7 @@ _do_read_vpn_details_impl1(const char              *file,
             g_assert(_d->key);                                                                \
             g_assert(_d->val);                                                                \
             _v = g_hash_table_lookup(_hash, _d->key);                                         \
-            if (!nm_streq0(_v, _d->val))                                                      \
+            if (!nm_streq0(_v, _d->val)) {                                                    \
                 g_error("%s:%d: hash '%s' contains data key '%s' with value %s%s%s but we "   \
                         "expected '%s'",                                                      \
                         file,                                                                 \
@@ -2351,14 +2352,17 @@ _do_read_vpn_details_impl1(const char              *file,
                         _d->key,                                                              \
                         NM_PRINT_FMT_QUOTE_STRING(_v),                                        \
                         _d->val);                                                             \
+            }                                                                                 \
         }                                                                                     \
                                                                                               \
         g_assert_cmpint(g_hash_table_size(_hash), ==, _expected_len);                         \
     }                                                                                         \
     G_STMT_END
 
+    NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
     _assert_hash(data, expected_data, expected_data_len);
     _assert_hash(secrets, expected_secrets, expected_secrets_len);
+    NM_PRAGMA_WARNING_REENABLE
 
 #undef _assert_hash
     return TRUE;
@@ -3049,10 +3053,12 @@ check_dbus_properties:
                     break;
                 p_expected_type++;
                 if (p_expected_type >= &expected_types[G_N_ELEMENTS(expected_types)]) {
+                    NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
                     g_error("D-Bus type \"%s\" is not implemented (in property %s.%s)",
                             (const char *) mpr->dbus_type,
                             mif->dbus_iface_name,
                             mpr->dbus_property_name);
+                    NM_PRAGMA_WARNING_REENABLE
                 }
             }
 
@@ -3151,6 +3157,7 @@ check_dbus_properties:
                             break;
                     }
                     if (p_expected_type_2 >= &expected_types[G_N_ELEMENTS(expected_types)]) {
+                        NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
                         g_error("D-Bus property \"%s.%s\" (type \"%s\") maps to property \"%s\", "
                                 "but that has an unexpected property type %s (expected %s)",
                                 mif->dbus_iface_name,
@@ -3159,6 +3166,7 @@ check_dbus_properties:
                                 pspec->name,
                                 g_type_name(pspec->value_type),
                                 g_type_name(p_expected_type->default_gtype));
+                        NM_PRAGMA_WARNING_REENABLE
                     }
                 }
 
diff --git a/src/libnm-client-test/nm-test-utils-impl.c b/src/libnm-client-test/nm-test-utils-impl.c
index ef98d9c221..ad642d2530 100644
--- a/src/libnm-client-test/nm-test-utils-impl.c
+++ b/src/libnm-client-test/nm-test-utils-impl.c
@@ -159,7 +159,9 @@ nmtstc_service_init(void)
                  * via pygobject. */
                 return NULL;
             }
+            NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
             g_error("test service %s exited with error code %d", NMTSTC_NM_SERVICE, data.exit_code);
+            NM_PRAGMA_WARNING_REENABLE
         }
     }
 
diff --git a/src/libnm-core-impl/tests/test-setting.c b/src/libnm-core-impl/tests/test-setting.c
index 490196a69b..788f218d2f 100644
--- a/src/libnm-core-impl/tests/test-setting.c
+++ b/src/libnm-core-impl/tests/test-setting.c
@@ -4774,10 +4774,12 @@ check_done:;
                         g_assert(NM_IS_SETTING_VPN(setting));
                         g_assert_cmpstr(sip->name, ==, NM_SETTING_VPN_SECRETS);
                     } else {
+                        NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
                         g_error("secret %s.%s is of unexpected property type %s",
                                 nm_setting_get_name(setting),
                                 sip->name,
                                 g_type_name(sip->param_spec->value_type));
+                        NM_PRAGMA_WARNING_REENABLE
                     }
                 }
             }
@@ -4900,12 +4902,14 @@ check_done:;
 
                 /* the property-types with same content should all be shared. Here we have two that
                  * are the same content, but different instances. Bug. */
+                NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
                 g_error("The identical property type for D-Bus type \"%s\" is used by: %s and %s. "
                         "If a NMSettInfoPropertType is identical, it should be shared by creating "
                         "a common instance of the property type",
                         (const char *) pt->dbus_type,
                         _PROP_IDX_OWNER(h_property_types, pt),
                         _PROP_IDX_OWNER(h_property_types, pt_2));
+                NM_PRAGMA_WARNING_REENABLE
             }
         }
     }
diff --git a/src/libnm-glib-aux/nm-shared-utils.c b/src/libnm-glib-aux/nm-shared-utils.c
index 6e6fed12c2..262be5feea 100644
--- a/src/libnm-glib-aux/nm-shared-utils.c
+++ b/src/libnm-glib-aux/nm-shared-utils.c
@@ -1130,6 +1130,7 @@ nm_utils_parse_inaddr_bin_full(int         addr_family,
 
 #if NM_MORE_ASSERTS > 10
     if (addr_family == AF_INET) {
+        NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
         gs_free_error GError *error = NULL;
         in_addr_t             a;
 
@@ -1145,6 +1146,7 @@ nm_utils_parse_inaddr_bin_full(int         addr_family,
                     error->message);
         }
         nm_assert(addrbin.addr4 == a);
+        NM_PRAGMA_WARNING_REENABLE
     }
 #endif
 
diff --git a/src/libnm-glib-aux/nm-test-utils.h b/src/libnm-glib-aux/nm-test-utils.h
index caf43d5f48..2dfe9e323e 100644
--- a/src/libnm-glib-aux/nm-test-utils.h
+++ b/src/libnm-glib-aux/nm-test-utils.h
@@ -1714,8 +1714,11 @@ __nmtst_spawn_sync(const char *working_directory,
                            standard_err,
                            &exit_status,
                            &error);
-    if (!success)
+    if (!success) {
+        NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
         g_error("nmtst_spawn_sync(%s): %s", ((char **) argv->pdata)[0], error->message);
+        NM_PRAGMA_WARNING_REENABLE
+    }
     g_assert(!error);
 
     g_assert(!standard_out || *standard_out);
@@ -1844,7 +1847,8 @@ _nmtst_assert_resolve_relative_path_equals(const char *f1,
 
     /* Fixme: later we might need to coalesce repeated '/', "./", and "../".
      * For now, it's good enough. */
-    if (g_strcmp0(p1, p2) != 0)
+    if (g_strcmp0(p1, p2) != 0) {
+        NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
         g_error("%s:%d : filenames don't match \"%s\" vs. \"%s\" // \"%s\" - \"%s\"",
                 file,
                 line,
@@ -1852,6 +1856,8 @@ _nmtst_assert_resolve_relative_path_equals(const char *f1,
                 f2,
                 p1,
                 p2);
+        NM_PRAGMA_WARNING_REENABLE
+    }
 }
 #define nmtst_assert_resolve_relative_path_equals(f1, f2) \
     _nmtst_assert_resolve_relative_path_equals(f1, f2, __FILE__, __LINE__);
@@ -2404,9 +2410,11 @@ _nmtst_assert_connection_has_settings(NMConnection *connection,
     settings = nm_connection_get_settings(connection, &len);
     for (i = 0; i < len; i++) {
         if (!g_hash_table_remove(names, nm_setting_get_name(settings[i])) && has_at_most) {
+            NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
             g_error(
                 "nmtst_assert_connection_has_settings(): has setting \"%s\" which is not expected",
                 nm_setting_get_name(settings[i]));
+            NM_PRAGMA_WARNING_REENABLE
         }
     }
     if (g_hash_table_size(names) > 0 && has_at_least) {
@@ -2419,11 +2427,13 @@ _nmtst_assert_connection_has_settings(NMConnection *connection,
             settings_names[i] = nm_setting_get_name(settings[i]);
         has_str = g_strjoinv(" ", (char **) settings_names);
 
+        NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
         g_error("nmtst_assert_connection_has_settings(): the setting lacks %u expected settings "
                 "(expected: [%s] vs. has: [%s])",
                 g_hash_table_size(names),
                 expected_str,
                 has_str);
+        NM_PRAGMA_WARNING_REENABLE
     }
 }
 #define nmtst_assert_connection_has_settings(connection, ...) \
diff --git a/src/libnm-platform/tests/test-nm-platform.c b/src/libnm-platform/tests/test-nm-platform.c
index d4de0dd5ea..9ac69bdeda 100644
--- a/src/libnm-platform/tests/test-nm-platform.c
+++ b/src/libnm-platform/tests/test-nm-platform.c
@@ -131,11 +131,13 @@ test_nmp_link_mode_all_advertised_modes_bits(void)
 
     for (i = 0; i < (int) G_N_ELEMENTS(_nmp_link_mode_all_advertised_modes); i++) {
         if (flags[i] != _nmp_link_mode_all_advertised_modes[i]) {
+            NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
             g_error("_nmp_link_mode_all_advertised_modes[%d] should be 0x%0x but is 0x%0x "
                     "(according to the bits in _nmp_link_mode_all_advertised_modes_bits)",
                     i,
                     flags[i],
                     _nmp_link_mode_all_advertised_modes[i]);
+            NM_PRAGMA_WARNING_REENABLE
         }
     }
 }
diff --git a/src/nm-dispatcher/tests/test-dispatcher-envp.c b/src/nm-dispatcher/tests/test-dispatcher-envp.c
index f53bb1c137..51d31544ec 100644
--- a/src/nm-dispatcher/tests/test-dispatcher-envp.c
+++ b/src/nm-dispatcher/tests/test-dispatcher-envp.c
@@ -530,8 +530,11 @@ test_generic(const char *file, const char *override_vpn_ip_iface)
 
     g_assert((!denv && error_message) || (denv && !error_message));
 
-    if (error_message)
+    if (error_message) {
+        NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
         g_error("FAILED: %s", error_message);
+        NM_PRAGMA_WARNING_REENABLE
+    }
 
     if (g_strv_length(denv) != g_hash_table_size(expected_env)) {
         _print_env(NM_CAST_STRV_CC(denv), expected_env);
@@ -552,8 +555,10 @@ test_generic(const char *file, const char *override_vpn_ip_iface)
 
         foo = g_hash_table_lookup(expected_env, i_value);
         if (!foo) {
+            NM_PRAGMA_WARNING_DISABLE_DANGLING_POINTER
             _print_env(NM_CAST_STRV_CC(denv), expected_env);
             g_error("Failed to find %s in environment", i_value);
+            NM_PRAGMA_WARNING_REENABLE
         }
     }