Disable -Wdiv-by-zero for some tests in stdio-common/tst-unlockedio.c.

This patch uses diagnostic control pragmas to disable some
division-by-zero warnings in stdio-common/tst-unlockedio.c.  This is
another test where disabling warnings using diagnostic pragmas seems
appropriate (the warnings are not wildly inappropriate for what the
test deliberately does; the deliberate use of unusual arguments to the
macros being tested means that changing the arguments in a way that
avoids the warning would also unduly perturb what is being tested).

Tested for x86_64.

	* stdio-common/tst-unlockedio.c: Include <libc-internal.h>.
	(do_test): Disable -Wdiv-by-zero around some calls to
	fwrite_unlocked and fread_unlocked.
This commit is contained in:
Joseph Myers 2014-12-10 00:43:36 +00:00
parent 2084e7ca4d
commit c81e9deba2
2 changed files with 17 additions and 0 deletions

View File

@ -1,5 +1,9 @@
2014-12-10 Joseph Myers <joseph@codesourcery.com> 2014-12-10 Joseph Myers <joseph@codesourcery.com>
* stdio-common/tst-unlockedio.c: Include <libc-internal.h>.
(do_test): Disable -Wdiv-by-zero around some calls to
fwrite_unlocked and fread_unlocked.
* include/libc-internal.h (DIAG_PUSH_NEEDS_COMMENT): New macro. * include/libc-internal.h (DIAG_PUSH_NEEDS_COMMENT): New macro.
(DIAG_POP_NEEDS_COMMENT): Likewise. (DIAG_POP_NEEDS_COMMENT): Likewise.
(_DIAG_STR1): Likewise. (_DIAG_STR1): Likewise.

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@ -20,6 +20,7 @@
#include <stdlib.h> #include <stdlib.h>
#include <stdio.h> #include <stdio.h>
#include <string.h> #include <string.h>
#include <libc-internal.h>
int fd; int fd;
static void do_prepare (void); static void do_prepare (void);
@ -44,6 +45,13 @@ do_test (void)
f = fp; f = fp;
cp = blah; cp = blah;
/* These tests deliberately use fwrite_unlocked with the size
argument specified as 0, which results in "division by zero"
warnings from the expansion of that macro (in code that is not
evaluated for a size of 0). This applies to the tests of
fread_unlocked below as well. */
DIAG_PUSH_NEEDS_COMMENT;
DIAG_IGNORE_NEEDS_COMMENT (4.9, "-Wdiv-by-zero");
if (ftello (fp) != 0 if (ftello (fp) != 0
|| fwrite_unlocked (blah, blah - blah, strlen (blah), f++) != 0 || fwrite_unlocked (blah, blah - blah, strlen (blah), f++) != 0
|| f != fp + 1 || f != fp + 1
@ -59,6 +67,7 @@ do_test (void)
puts ("One of fwrite_unlocked tests failed"); puts ("One of fwrite_unlocked tests failed");
exit (1); exit (1);
} }
DIAG_POP_NEEDS_COMMENT;
if (fwrite_unlocked (blah, 1, strlen (blah) - 2, fp) != strlen (blah) - 2) if (fwrite_unlocked (blah, 1, strlen (blah) - 2, fp) != strlen (blah) - 2)
{ {
@ -93,6 +102,9 @@ do_test (void)
f = fp; f = fp;
wp = buf; wp = buf;
memset (buf, ' ', sizeof (buf)); memset (buf, ' ', sizeof (buf));
/* See explanation above. */
DIAG_PUSH_NEEDS_COMMENT;
DIAG_IGNORE_NEEDS_COMMENT (4.9, "-Wdiv-by-zero");
if (ftello (fp) != 0 if (ftello (fp) != 0
|| fread_unlocked (buf, buf - buf, strlen (blah), f++) != 0 || fread_unlocked (buf, buf - buf, strlen (blah), f++) != 0
|| f != fp + 1 || f != fp + 1
@ -109,6 +121,7 @@ do_test (void)
puts ("One of fread_unlocked tests failed"); puts ("One of fread_unlocked tests failed");
exit (1); exit (1);
} }
DIAG_POP_NEEDS_COMMENT;
if (fread_unlocked (buf, 1, strlen (blah) - 2, fp) != strlen (blah) - 2) if (fread_unlocked (buf, 1, strlen (blah) - 2, fp) != strlen (blah) - 2)
{ {