From 0c3717e7827969895f6ffe57c66e1612358ce6b1 Mon Sep 17 00:00:00 2001
From: Joseph Myers <joseph@codesourcery.com>
Date: Fri, 22 May 2015 20:13:44 +0000
Subject: Fix ldbl-128 / ldbl-128ibm tanl for -Wuninitialized.

The ldbl-128 and ldbl-128ibm implementations of tanl produce
uninitialized variable warnings with -Wuninitialized because of a
variable that is initialized only conditionally, then used under the
same conditions under which it is set.  This patch uses DIAG_* macros
to suppress those warnings.

Tested for powerpc and mips64.

	* sysdeps/ieee754/ldbl-128/k_tanl.c: Include <libc-internal.h>.
	(__kernel_tanl): Ignore uninitialized warnings around use of SIGN.
	* sysdeps/ieee754/ldbl-128ibm/k_tanl.c: Include <libc-internal.h>.
	(__kernel_tanl): Ignore uninitialized warnings around use of SIGN.
---
 sysdeps/ieee754/ldbl-128/k_tanl.c    | 12 ++++++++++++
 sysdeps/ieee754/ldbl-128ibm/k_tanl.c | 12 ++++++++++++
 2 files changed, 24 insertions(+)

(limited to 'sysdeps/ieee754')

diff --git a/sysdeps/ieee754/ldbl-128/k_tanl.c b/sysdeps/ieee754/ldbl-128/k_tanl.c
index 140ce95..dfba2d9 100644
--- a/sysdeps/ieee754/ldbl-128/k_tanl.c
+++ b/sysdeps/ieee754/ldbl-128/k_tanl.c
@@ -56,6 +56,7 @@
  *		       = 1 - 2*(tan(y) - (tan(y)^2)/(1+tan(y)))
  */
 
+#include <libc-internal.h>
 #include <math.h>
 #include <math_private.h>
 static const long double
@@ -129,8 +130,19 @@ __kernel_tanl (long double x, long double y, int iy)
     {
       v = (long double) iy;
       w = (v - 2.0 * (x - (w * w / (w + v) - r)));
+      /* SIGN is set for arguments that reach this code, but not
+	 otherwise, resulting in warnings that it may be used
+	 uninitialized although in the cases where it is used it has
+	 always been set.  */
+      DIAG_PUSH_NEEDS_COMMENT;
+#if __GNUC_PREREQ (4, 7)
+      DIAG_IGNORE_NEEDS_COMMENT (5, "-Wmaybe-uninitialized");
+#else
+      DIAG_IGNORE_NEEDS_COMMENT (5, "-Wuninitialized");
+#endif
       if (sign < 0)
 	w = -w;
+      DIAG_POP_NEEDS_COMMENT;
       return w;
     }
   if (iy == 1)
diff --git a/sysdeps/ieee754/ldbl-128ibm/k_tanl.c b/sysdeps/ieee754/ldbl-128ibm/k_tanl.c
index bcf8b5e..7f1caee 100644
--- a/sysdeps/ieee754/ldbl-128ibm/k_tanl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/k_tanl.c
@@ -56,6 +56,7 @@
  *		       = 1 - 2*(tan(y) - (tan(y)^2)/(1+tan(y)))
  */
 
+#include <libc-internal.h>
 #include <math.h>
 #include <math_private.h>
 static const long double
@@ -129,8 +130,19 @@ __kernel_tanl (long double x, long double y, int iy)
     {
       v = (long double) iy;
       w = (v - 2.0 * (x - (w * w / (w + v) - r)));
+      /* SIGN is set for arguments that reach this code, but not
+	 otherwise, resulting in warnings that it may be used
+	 uninitialized although in the cases where it is used it has
+	 always been set.  */
+      DIAG_PUSH_NEEDS_COMMENT;
+#if __GNUC_PREREQ (4, 7)
+      DIAG_IGNORE_NEEDS_COMMENT (5, "-Wmaybe-uninitialized");
+#else
+      DIAG_IGNORE_NEEDS_COMMENT (5, "-Wuninitialized");
+#endif
       if (sign < 0)
 	w = -w;
+      DIAG_POP_NEEDS_COMMENT;
       return w;
     }
   if (iy == 1)
-- 
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