Several fixlets for GCC warnings (#36051)

Replaces #36043 and #36039.

meson.build

@@ -516,9 +516,6 @@ add_project_link_arguments(
 userspace_c_args += cc.get_supported_arguments(possible_cc_flags)
 userspace_c_ld_args += cc.get_supported_link_arguments(possible_link_flags)
 
-have = cc.has_argument('-Wzero-length-bounds')
-conf.set10('HAVE_ZERO_LENGTH_BOUNDS', have)
-
 if cc.compiles('''
    #include <time.h>
    #include <inttypes.h>
@@ -538,14 +535,19 @@ endif
 
 cpp = ' '.join(cc.cmd_array() + get_option('c_args')) + ' -E'
 
-has_wstringop_truncation = cc.has_argument('-Wstringop-truncation')
+# new in GCC 10
+have = cc.has_argument('-Wzero-length-bounds')
+conf.set10('HAVE_WARNING_ZERO_LENGTH_BOUNDS', have)
+
+# new in GCC 15
+have = cc.has_argument('-Wzero-as-null-pointer-constant')
+conf.set10('HAVE_WARNING_ZERO_AS_NULL_POINTER_CONSTANT', have)
 
 #####################################################################
 # compilation result tests
 
 conf.set('_GNU_SOURCE', 1)
 conf.set('__SANE_USERSPACE_TYPES__', true)
-conf.set10('HAVE_WSTRINGOP_TRUNCATION', has_wstringop_truncation)
 
 conf.set('SIZEOF_DEV_T', cc.sizeof('dev_t', prefix : '#include <sys/types.h>'))
 conf.set('SIZEOF_INO_T', cc.sizeof('ino_t', prefix : '#include <sys/types.h>'))

src/basic/macro.h

@@ -30,15 +30,6 @@
 #define _function_no_sanitize_float_cast_overflow_
 #endif
 
-#if HAVE_WSTRINGOP_TRUNCATION
-#  define DISABLE_WARNING_STRINGOP_TRUNCATION                           \
-        _Pragma("GCC diagnostic push");                                 \
-        _Pragma("GCC diagnostic ignored \"-Wstringop-truncation\"")
-#else
-#  define DISABLE_WARNING_STRINGOP_TRUNCATION                           \
-        _Pragma("GCC diagnostic push")
-#endif
-
 /* test harness */
 #define EXIT_TEST_SKIP 77
 

src/boot/meson.build

@@ -74,6 +74,12 @@ if conf.get('ENABLE_BOOTLOADER') != 1
 endif
 
 efi_conf = configuration_data()
+
+# import several configs from userspace
+foreach name : ['HAVE_WARNING_ZERO_LENGTH_BOUNDS', 'HAVE_WARNING_ZERO_AS_NULL_POINTER_CONSTANT']
+        efi_conf.set10(name, conf.get(name) == 1)
+endforeach
+
 efi_conf.set10('ENABLE_TPM', get_option('tpm'))
 
 foreach ctype : ['color-normal', 'color-entry', 'color-highlight', 'color-edit']

src/fundamental/macro-fundamental.h

@@ -48,6 +48,28 @@
         _Pragma("GCC diagnostic push");                                 \
         _Pragma("GCC diagnostic ignored \"-Waddress\"")
 
+#define DISABLE_WARNING_STRINGOP_TRUNCATION                             \
+        _Pragma("GCC diagnostic push");                                 \
+        _Pragma("GCC diagnostic ignored \"-Wstringop-truncation\"")
+
+#if HAVE_WARNING_ZERO_LENGTH_BOUNDS
+#  define DISABLE_WARNING_ZERO_LENGTH_BOUNDS                            \
+        _Pragma("GCC diagnostic push");                                 \
+        _Pragma("GCC diagnostic ignored \"-Wzero-length-bounds\"")
+#else
+#  define DISABLE_WARNING_ZERO_LENGTH_BOUNDS                            \
+        _Pragma("GCC diagnostic push")
+#endif
+
+#if HAVE_WARNING_ZERO_AS_NULL_POINTER_CONSTANT
+#  define DISABLE_WARNING_ZERO_AS_NULL_POINTER_CONSTANT                 \
+        _Pragma("GCC diagnostic push");                                 \
+        _Pragma("GCC diagnostic ignored \"-Wzero-as-null-pointer-constant\"")
+#else
+#  define DISABLE_WARNING_ZERO_AS_NULL_POINTER_CONSTANT                 \
+        _Pragma("GCC diagnostic push")
+#endif
+
 #define REENABLE_WARNING                                                \
         _Pragma("GCC diagnostic pop")
 

src/nss-systemd/nss-systemd.c

@@ -101,6 +101,9 @@ typedef struct GetentData {
         bool by_membership;
 } GetentData;
 
+/* On current glibc PTHREAD_MUTEX_INITIALIZER is defined in a way incompatible with
+ * -Wzero-as-null-pointer-constant, work around this for now. */
+DISABLE_WARNING_ZERO_AS_NULL_POINTER_CONSTANT;
 static GetentData getpwent_data = {
         .mutex = PTHREAD_MUTEX_INITIALIZER,
 };
@@ -116,6 +119,7 @@ static GetentData getspent_data = {
 static GetentData getsgent_data = {
         .mutex = PTHREAD_MUTEX_INITIALIZER,
 };
+REENABLE_WARNING;
 
 static void setup_logging_once(void) {
         static pthread_once_t once = PTHREAD_ONCE_INIT;

src/resolve/resolved-dns-dnssec.c

@@ -15,11 +15,10 @@
 #include "string-table.h"
 
 #if PREFER_OPENSSL && OPENSSL_VERSION_MAJOR >= 3
-#  pragma GCC diagnostic push
-#    pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+DISABLE_WARNING_DEPRECATED_DECLARATIONS;
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(RSA*, RSA_free, NULL);
 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(EC_KEY*, EC_KEY_free, NULL);
-#  pragma GCC diagnostic pop
+REENABLE_WARNING;
 #endif
 
 #define VERIFY_RRS_MAX 256
@@ -101,8 +100,7 @@ static int dnssec_rsa_verify_raw(
         int r;
 
 #if PREFER_OPENSSL
-#  pragma GCC diagnostic push
-#    pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+        DISABLE_WARNING_DEPRECATED_DECLARATIONS;
         _cleanup_(RSA_freep) RSA *rpubkey = NULL;
         _cleanup_(EVP_PKEY_freep) EVP_PKEY *epubkey = NULL;
         _cleanup_(EVP_PKEY_CTX_freep) EVP_PKEY_CTX *ctx = NULL;
@@ -153,7 +151,7 @@ static int dnssec_rsa_verify_raw(
                 return log_debug_errno(SYNTHETIC_ERRNO(EIO),
                                        "Signature verification failed: 0x%lx", ERR_get_error());
 
-#  pragma GCC diagnostic pop
+        REENABLE_WARNING;
 #else
         gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL;
         gcry_mpi_t n = NULL, e = NULL, s = NULL;
@@ -303,8 +301,7 @@ static int dnssec_ecdsa_verify_raw(
         int k;
 
 #if PREFER_OPENSSL
-#  pragma GCC diagnostic push
-#    pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+        DISABLE_WARNING_DEPRECATED_DECLARATIONS;
         _cleanup_(EC_GROUP_freep) EC_GROUP *ec_group = NULL;
         _cleanup_(EC_POINT_freep) EC_POINT *p = NULL;
         _cleanup_(EC_KEY_freep) EC_KEY *eckey = NULL;
@@ -365,7 +362,7 @@ static int dnssec_ecdsa_verify_raw(
                 return log_debug_errno(SYNTHETIC_ERRNO(EIO),
                                        "Signature verification failed: 0x%lx", ERR_get_error());
 
-#  pragma GCC diagnostic pop
+        REENABLE_WARNING;
 #else
         gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL;
         gcry_mpi_t q = NULL, r = NULL, s = NULL;

src/shared/ethtool-util.c

@@ -11,6 +11,7 @@
 #include "extract-word.h"
 #include "fd-util.h"
 #include "log.h"
+#include "macro-fundamental.h"
 #include "memory-util.h"
 #include "socket-util.h"
 #include "string-table.h"
@@ -452,12 +453,9 @@ static int get_stringset(int ethtool_fd, const char *ifname, enum ethtool_string
         if (buffer.info.sset_mask == 0)
                 return -EOPNOTSUPP;
 
-#pragma GCC diagnostic push
-#if HAVE_ZERO_LENGTH_BOUNDS
-#  pragma GCC diagnostic ignored "-Wzero-length-bounds"
-#endif
+        DISABLE_WARNING_ZERO_LENGTH_BOUNDS;
         len = buffer.info.data[0];
-#pragma GCC diagnostic pop
+        REENABLE_WARNING;
         if (len == 0)
                 return -EOPNOTSUPP;