Disable strncat test array-bounds warnings for GCC 8.

Some strncat tests fail to build with GCC 8 because of -Warray-bounds
warnings.  These tests are deliberately test over-large size arguments
passed to strncat, and already disable -Wstringop-overflow warnings,
but now the warnings for these tests come under -Warray-bounds so that
option needs disabling for them as well, which this patch does (with
an update on the comments; the DIAG_IGNORE_NEEDS_COMMENT call for
-Warray-bounds doesn't need to be conditional itself, because that
option is supported by all versions of GCC that can build glibc).

Tested compilation with build-many-glibcs.py for aarch64-linux-gnu.

	* string/tester.c (test_strncat): Also disable -Warray-bounds
	warnings for two tests.

(cherry picked from commit 1421f39b7eadd3b5fbd2a3f2da1fc006b69fbc42)

diff --git a/ChangeLog b/ChangeLog
index 3d3d364b4fa2ad7e85307d95e2d0ea475500a8ea..61a3c872a5af6c917f28de519efb739d216be9e5 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2017-12-18  Joseph Myers  <joseph@codesourcery.com>
+
+       * string/tester.c (test_strncat): Also disable -Warray-bounds
+       warnings for two tests.
+
 2017-11-14  Joseph Myers  <joseph@codesourcery.com>
 
        * string/tester.c (test_stpncpy): Disable -Wstringop-truncation

diff --git a/string/tester.c b/string/tester.c
index 66b11515b05d99278a95b3bfaf0c7b740d5b53f4..02ea8e1e16544e5439579be2174cfc856d6441a3 100644 (file)
--- a/string/tester.c
+++ b/string/tester.c
@@ -387,9 +387,11 @@ test_strncat (void)
   DIAG_PUSH_NEEDS_COMMENT;
 #if __GNUC_PREREQ (7, 0)
   /* GCC 7 warns about the size passed to strncat being larger than
-     the size of the buffer; this is deliberately tested here..  */
+     the size of the buffer; this is deliberately tested here; GCC 8
+     gives a -Warray-bounds warning about this.  */
   DIAG_IGNORE_NEEDS_COMMENT (7, "-Wstringop-overflow=");
 #endif
+  DIAG_IGNORE_NEEDS_COMMENT (8, "-Warray-bounds");
   (void) strncat (one, two, 99);
   DIAG_POP_NEEDS_COMMENT;
   equal (one, "ghef", 5);                      /* Basic test encore. */
@@ -480,9 +482,11 @@ test_strncat (void)
 #if __GNUC_PREREQ (7, 0)
            /* GCC 7 warns about the size passed to strncat being
               larger than the size of the buffer; this is
-              deliberately tested here..  */
+              deliberately tested here; GCC 8 gives a -Warray-bounds
+              warning about this.  */
            DIAG_IGNORE_NEEDS_COMMENT (7, "-Wstringop-overflow=");
 #endif
+           DIAG_IGNORE_NEEDS_COMMENT (8, "-Warray-bounds");
            check (strncat (buf1 + n2, buf2 + n1, ~((size_t) 0) - n4)
                   == buf1 + n2, ntest);
            DIAG_POP_NEEDS_COMMENT;