Re: [PATCH] PR28901 -Wunused-variable ignores unused const initialised variables

[Mark Wielaard <mjw at redhat dot com>]

On Tue, 2015-09-15 at 10:20 -0700, Steve Ellcey wrote:
> On Tue, 2015-09-15 at 19:10 +0200, Jakub Jelinek wrote:
> > On Tue, Sep 15, 2015 at 10:02:15AM -0700, Steve Ellcey wrote:
> > > I am not sure I like this change.  It broke the GLIBC build for me on
> > > MIPS.  Basically GLIBC has a header file with initialized static
> > > constant globals (sysdeps/ieee754/dbl-64/atnat2.h contains tqpi1 and
> > > qpi1) and that header file is included in multiple .c files like
> > 
> > Multiple?  All I can see is e_atan2.c including that header file, nothing
> > else.
> 
> Whoops, bad assumption on my part.  I thought it must be included
> somewhere else, otherwise why put it in a header.

Yeah, odd. But it seems the issues the warning pointed out are real. I
build glibc and found 9 unused variables. They all look like they are
really not used in the code, so they can all just be removed. Someone of
course should double check they aren't unused by accident before
committing upstream.

Cheers,

Mark

diff --git a/math/atest-exp2.c b/math/atest-exp2.c
index 307c741..ffa73b1 100644
--- a/math/atest-exp2.c
+++ b/math/atest-exp2.c
@@ -53,11 +53,6 @@ static const mp1 mp_exp1 = {
            a784d904, 5190cfef, 324e7738, 926cfbe5, f4bf8d8d, 8c31d763)
 };
 
-static const mp1 mp_exp_m1 = {
-  CONSTSZ (0, 5e2d58d8, b3bcdf1a, badec782, 9054f90d, da9805aa, b56c7733,
-           3024b9d0, a507daed, b16400bf, 472b4215, b8245b66, 9d90d27a)
-};
-
 static const mp1 mp_log2 = {
   CONSTSZ (0, b17217f7, d1cf79ab, c9e3b398, 03f2f6af, 40f34326, 7298b62d,
            8a0d175b, 8baafa2b, e7b87620, 6debac98, 559552fb, 4afa1b10)
diff --git a/resolv/base64.c b/resolv/base64.c
index ea584ed..519e5d2 100644
--- a/resolv/base64.c
+++ b/resolv/base64.c
@@ -40,10 +40,6 @@
  * IF IBM IS APPRISED OF THE POSSIBILITY OF SUCH DAMAGES.
  */
 
-#if !defined(LINT) && !defined(CODECENTER)
-static const char rcsid[] = "$BINDId: base64.c,v 8.7 1999/10/13 16:39:33 vixie Exp $";
-#endif /* not lint */
-
 #include <sys/types.h>
 #include <sys/param.h>
 #include <sys/socket.h>
diff --git a/sysdeps/ieee754/dbl-64/atnat2.h b/sysdeps/ieee754/dbl-64/atnat2.h
index e0d65af..82943f9 100644
--- a/sysdeps/ieee754/dbl-64/atnat2.h
+++ b/sysdeps/ieee754/dbl-64/atnat2.h
@@ -65,10 +65,8 @@
 /**/ hpi1           = {{0x3c91a626, 0x33145c07} }, /*  pi/2-hpi     */
 /**/ mhpi           = {{0xbff921fb, 0x54442d18} }, /* -pi/2         */
 /**/ qpi            = {{0x3fe921fb, 0x54442d18} }, /*  pi/4         */
-/**/ qpi1           = {{0x3c81a626, 0x33145c07} }, /*  pi/4-qpi     */
 /**/ mqpi           = {{0xbfe921fb, 0x54442d18} }, /* -pi/4         */
 /**/ tqpi           = {{0x4002d97c, 0x7f3321d2} }, /*  3pi/4        */
-/**/ tqpi1          = {{0x3c9a7939, 0x4c9e8a0a} }, /*  3pi/4-tqpi   */
 /**/ mtqpi          = {{0xc002d97c, 0x7f3321d2} }, /* -3pi/4        */
 /**/ u1             = {{0x3c314c2a, 0x00000000} }, /*  9.377e-19    */
 /**/ u2             = {{0x3bf955e4, 0x00000000} }, /*  8.584e-20    */
@@ -129,10 +127,8 @@
 /**/ hpi1           = {{0x33145c07, 0x3c91a626} }, /*  pi/2-hpi     */
 /**/ mhpi           = {{0x54442d18, 0xbff921fb} }, /* -pi/2         */
 /**/ qpi            = {{0x54442d18, 0x3fe921fb} }, /*  pi/4         */
-/**/ qpi1           = {{0x33145c07, 0x3c81a626} }, /*  pi/4-qpi     */
 /**/ mqpi           = {{0x54442d18, 0xbfe921fb} }, /* -pi/4         */
 /**/ tqpi           = {{0x7f3321d2, 0x4002d97c} }, /*  3pi/4        */
-/**/ tqpi1          = {{0x4c9e8a0a, 0x3c9a7939} }, /*  3pi/4-tqpi   */
 /**/ mtqpi          = {{0x7f3321d2, 0xc002d97c} }, /* -3pi/4        */
 /**/ u1             = {{0x00000000, 0x3c314c2a} }, /*  9.377e-19    */
 /**/ u2             = {{0x00000000, 0x3bf955e4} }, /*  8.584e-20    */
diff --git a/sysdeps/ieee754/dbl-64/uexp.h b/sysdeps/ieee754/dbl-64/uexp.h
index 6817eaf..42b21f2 100644
--- a/sysdeps/ieee754/dbl-64/uexp.h
+++ b/sysdeps/ieee754/dbl-64/uexp.h
@@ -29,7 +29,7 @@
 
 #include "mydefs.h"
 
-const static double one = 1.0, zero = 0.0, hhuge = 1.0e300, tiny = 1.0e-300,
+const static double zero = 0.0, hhuge = 1.0e300, tiny = 1.0e-300,
 err_0 = 1.000014, err_1 = 0.000016;
 const static int4 bigint = 0x40862002,
              badint = 0x40876000,smallint = 0x3C8fffff;
diff --git a/sysdeps/ieee754/dbl-64/upow.h b/sysdeps/ieee754/dbl-64/upow.h
index c8569a9..b4911e5 100644
--- a/sysdeps/ieee754/dbl-64/upow.h
+++ b/sysdeps/ieee754/dbl-64/upow.h
@@ -34,7 +34,6 @@
 /**/ nZERO	    = {{0x80000000, 0}},	  /* -0.0          */
 /**/ INF            = {{0x7ff00000, 0x00000000}}, /* INF           */
 /**/ nINF           = {{0xfff00000, 0x00000000}}, /* -INF          */
-/**/ sqrt_2         = {{0x3ff6a09e, 0x667f3bcc}}, /* sqrt(2)       */
 /**/ ln2a           = {{0x3fe62e42, 0xfefa3800}}, /* ln(2) 43 bits */
 /**/ ln2b           = {{0x3d2ef357, 0x93c76730}}, /* ln(2)-ln2a    */
 /**/ bigu           = {{0x4297ffff, 0xfffffd2c}}, /* 1.5*2**42 -724*2**-10  */
@@ -48,7 +47,6 @@
 /**/ nZERO	    = {{0, 0x80000000}},	  /* -0.0          */
 /**/ INF            = {{0x00000000, 0x7ff00000}}, /* INF           */
 /**/ nINF           = {{0x00000000, 0xfff00000}}, /* -INF           */
-/**/ sqrt_2         = {{0x667f3bcc, 0x3ff6a09e}}, /* sqrt(2)       */
 /**/ ln2a           = {{0xfefa3800, 0x3fe62e42}}, /* ln(2) 43 bits */
 /**/ ln2b           = {{0x93c76730, 0x3d2ef357}}, /* ln(2)-ln2a    */
 /**/ bigu           = {{0xfffffd2c, 0x4297ffff}}, /* 1.5*2**42 -724*2**-10  */
diff --git a/sysdeps/ieee754/flt-32/e_log10f.c b/sysdeps/ieee754/flt-32/e_log10f.c
index 96f0e81..1daeef7 100644
--- a/sysdeps/ieee754/flt-32/e_log10f.c
+++ b/sysdeps/ieee754/flt-32/e_log10f.c
@@ -22,8 +22,6 @@ ivln10     =  4.3429449201e-01, /* 0x3ede5bd9 */
 log10_2hi  =  3.0102920532e-01, /* 0x3e9a2080 */
 log10_2lo  =  7.9034151668e-07; /* 0x355427db */
 
-static const float zero   =  0.0;
-
 float
 __ieee754_log10f(float x)
 {
diff --git a/timezone/private.h b/timezone/private.h
index 4e8f4ae..ed19e06 100644
--- a/timezone/private.h
+++ b/timezone/private.h
@@ -326,16 +326,6 @@ const char *	scheck(const char * string, const char * format);
 #define TYPE_SIGNED(type) (((type) -1) < 0)
 #endif /* !defined TYPE_SIGNED */
 
-/* The minimum and maximum finite time values.  */
-static time_t const time_t_min =
-  (TYPE_SIGNED(time_t)
-   ? (time_t) -1 << (CHAR_BIT * sizeof (time_t) - 1)
-   : 0);
-static time_t const time_t_max =
-  (TYPE_SIGNED(time_t)
-   ? - (~ 0 < 0) - ((time_t) -1 << (CHAR_BIT * sizeof (time_t) - 1))
-   : -1);
-
 #ifndef INT_STRLEN_MAXIMUM
 /*
 ** 302 / 1000 is log10(2.0) rounded up.