diff mbox

[PATCHv3] S390: Fix build failure in test string/tst-endian.c with gcc 6.

Message ID n7t7a5$73n$1@ger.gmane.org
State Committed
Headers show

Commit Message

Stefan Liebler Jan. 22, 2016, 12:28 p.m. UTC
On 01/21/2016 05:44 PM, Mike Frysinger wrote:
> On 21 Jan 2016 17:38, Stefan Liebler wrote:
>> This patch suppresses these warnings with DIAG_* macros.
>> The conditional #if __GNUC_PREREQ (6, 0) is needed, because an older gcc
>> would warn about:
>> tst-endian.c: In function ‘do_test’:
>> tst-endian.c:18:4: warning: unknown option after ‘#pragma GCC
>> diagnostic’ kind [-Wpragmas]
>>       DIAG_IGNORE_NEEDS_COMMENT (6, "-Wtautological-compare");
>>       ^
>
> you can at least do it once at the top via a local define:
> /* big comment block */
> #if __GNUC_PREREQ (6, 0)
> # define DIAG_IGNORE_NEEDS_COMMENT_AUTOLOGICAL_COMPARE() \
>    DIAG_IGNORE_NEEDS_COMMENT (6, "-Wtautological-compare");
> #else
> # define DIAG_IGNORE_NEEDS_COMMENT_AUTOLOGICAL_COMPARE()
> #endif
>
> then the inline usage is simple
> -mike
>
That's a good point.
Here is the updated patch.

Ok to commit?

Bye Stefan

ChangeLog:

	* string/tst-endian.c: Include <libc-internal.h>
	(do_test): Ignore tautological-compare warnings around
	"htobeXX (beXXtoh (i)) != i" and
	"htoleXX (leXXtoh (i)) != i" if-statements.

Comments

Mike Frysinger Jan. 22, 2016, 7:55 p.m. UTC | #1
On 22 Jan 2016 13:28, Stefan Liebler wrote:
> Ok to commit?

seems fine to me
-mike
diff mbox

Patch

diff --git a/string/tst-endian.c b/string/tst-endian.c
index 8684bb2..7d39131 100644
--- a/string/tst-endian.c
+++ b/string/tst-endian.c
@@ -3,6 +3,20 @@ 
 #include <inttypes.h>
 #include <stdio.h>
 #include <stdint.h>
+#include <libc-internal.h>
+
+#if __GNUC_PREREQ (6, 0)
+/* GCC 6.0 warns on big endian systems about:
+   htobeXX (beXXtoh (i)) != i
+   warning: self-comparison always evaluates to false [-Wtautological-compare]
+   because htobeXX(x) and beXXtoh(x) is defined to (x)
+   in string/endian.h on big endian systems.
+   The same applies to htoleXX/leXXtoh on little endian systems.  */
+# define DIAG_IGNORE_NEEDS_COMMENT_TAUTOLOGICAL_COMPARE() \
+  DIAG_IGNORE_NEEDS_COMMENT (6, "-Wtautological-compare")
+#else
+# define DIAG_IGNORE_NEEDS_COMMENT_TAUTOLOGICAL_COMPARE()
+#endif
 
 static int
 do_test (void)
@@ -13,6 +27,8 @@  do_test (void)
     {
       if (i < UINT64_C (65536))
 	{
+	  DIAG_PUSH_NEEDS_COMMENT;
+	  DIAG_IGNORE_NEEDS_COMMENT_TAUTOLOGICAL_COMPARE ();
 	  if (htobe16 (be16toh (i)) != i)
 	    {
 	      printf ("htobe16 (be16toh (%" PRIx64 ")) == %" PRIx16 "\n",
@@ -25,6 +41,7 @@  do_test (void)
 		      i, (uint16_t) htole16 (le16toh (i)));
 	      result = 1;
 	    }
+	  DIAG_POP_NEEDS_COMMENT;
 
 	  uint16_t n[2];
 	  n[__BYTE_ORDER == __LITTLE_ENDIAN] = bswap_16 (i);
@@ -45,6 +62,8 @@  do_test (void)
 
       if (i < UINT64_C (4294967296))
 	{
+	  DIAG_PUSH_NEEDS_COMMENT;
+	  DIAG_IGNORE_NEEDS_COMMENT_TAUTOLOGICAL_COMPARE ();
 	  if (htobe32 (be32toh (i)) != i)
 	    {
 	      printf ("htobe32 (be32toh (%" PRIx64 ")) == %" PRIx32 "\n",
@@ -57,6 +76,7 @@  do_test (void)
 		      i, (uint32_t) htole32 (le32toh (i)));
 	      result = 1;
 	    }
+	  DIAG_POP_NEEDS_COMMENT;
 
 	  uint32_t n[2];
 	  n[__BYTE_ORDER == __LITTLE_ENDIAN] = bswap_32 (i);
@@ -75,6 +95,8 @@  do_test (void)
 	    }
 	}
 
+      DIAG_PUSH_NEEDS_COMMENT;
+      DIAG_IGNORE_NEEDS_COMMENT_TAUTOLOGICAL_COMPARE ();
       if (htobe64 (be64toh (i)) != i)
 	{
 	  printf ("htobe64 (be64toh (%" PRIx64 ")) == %" PRIx64 "\n",
@@ -87,6 +109,7 @@  do_test (void)
 		  i, htole64 (le64toh (i)));
 	  result = 1;
 	}
+      DIAG_POP_NEEDS_COMMENT;
 
       uint64_t n[2];
       n[__BYTE_ORDER == __LITTLE_ENDIAN] = bswap_64 (i);