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authorUlrich Drepper <drepper@redhat.com>1997-07-22 00:10:33 +0000
committerUlrich Drepper <drepper@redhat.com>1997-07-22 00:10:33 +0000
commit60c966358ed6fa6ce3ded5426f46232cbfd8e0fd (patch)
tree2edfd4ad681692a2dbfdfcabaead5bca25ed2be5 /sysdeps/libm-ieee754
parent907a1bacf996264c3197342cfc565b1d4f840bfb (diff)
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1997-07-22 01:35  Ulrich Drepper  <drepper@cygnus.com>

	* Makerules (+make-deps): Use $(CFLAGS) in run of $(+mkdep) so
	that optimizing is also selected for dependency generation.

	* configure.in: Add machine description for TI c[34]x.

	* inet/Makefile (routines): Remove ntohl and ntohs.
	* inet/netinet/in.h: Use optimized version of hton? and ntoh?
	for little endian machines.
	* sysdeps/alpha/ntohl.s: Removed.
	* sysdeps/alpha/ntohs.s: Removed.
	* sysdeps/generic/ntohl.c: Removed.
	* sysdeps/generic/ntohs.c: Removed.
	* sysdeps/generic/htonl.c: Add aliases for ntohl.
	* sysdeps/vax/htonl.s: Likewise.
	* sysdeps/generic/htons.c: Add aliases for ntohs.
	* sysdeps/vax/htons.s: Likewise.
	* sysdeps/vax/ntohl.s: Removed.
	* sysdeps/vax/ntohs.s: Removed.
	* sysdeps/generic/bits/htontoh.h: New file.
	* sysdeps/i386/htonl.S: New file.
	* sysdeps/i386/htons.S: New file.
	* sysdeps/i386/i486/htonl.S: New file.

	* sysdeps/i386/fpu/bits/mathinline.h: Correct and optimized compare
	macros.

	* sysdeps/mips/dl-machine.h: Remove mips64 dependent parts.
	* sysdeps/mips/mips64/dl-machine.h: New file.

	* sysdeps/unix/sysv/linux/Makefile (sysdep_headers): Don't install
	syscall-list.h.

1997-07-12  Andreas Jaeger  <aj@arthur.rhein-neckar.de>

	* libc.map: Add missing symbol _obstack.

1997-07-14 08:22  H.J. Lu  <hjl@gnu.ai.mit.edu>

	* sysdeps/mips/rtld-parms: New.

	* sysdeps/unix/sysv/linux/mips/lxstat.h: Moved to
	* sysdeps/unix/sysv/linux/mips/lxstat.c: ...this.

	* sysdeps/unix/sysv/linux/mips/sgidef.h: Moved to
	* sysdeps/unix/sysv/linux/mips/sgidefs.h: ...this.

	* sysdeps/generic/dl-sysdep.c (_start): Change to ENTRY_POINT.

1997-07-17 08:39  H.J. Lu  <hjl@gnu.ai.mit.edu>

	* sysdeps/mips/dl-machine.h: Remove extra stuff.

1997-07-06 07:18  Geoff Keating  <geoffk@ozemail.com.au>

	* sysdeps/powerpc/bits/endian.h: Handle multiple endianess.

	* stdlib/grouping.h: Suppress gcc warning about testing
	unsigned char for less-than-zero.
	* stdio-common/printf_fp.c: Likewise.
	* stdio-common/vfprintf.c: Likewise.

	* sysdeps/powerpc/add_n.s: New file.
	* sysdeps/powerpc/sub_n.s: New file.
	* sysdeps/powerpc/lshift.s: Ported XCOFF->ELF (from GMP).
	* sysdeps/powerpc/mul_1.s: Ported XCOFF->ELF (from GMP).
	* sysdeps/powerpc/addmul_1.s: Ported XCOFF->ELF (from GMP).
	* sysdeps/powerpc/submul_1.s: Ported XCOFF->ELF (from GMP).
	* sysdeps/powerpc/rshift.s: Ported XCOFF->ELF (from GMP).

	* math/libm-test.c (cos_test, sin_test, sincos_test): Use
	precomputed pi/6 rather than having gcc calculate it, otherwise
	tests give inaccurate result due to inaccurate input.
	* math/libm.map: Add __fe_*_env constants to list of exported
	symbols.

	* sysdeps/libm-ieee754/s_isinf.c: Simplify, make faster.
	* sysdeps/libm-ieee754/s_isinff.c: Simplify, make faster.
	* sysdeps/libm-ieee754/s_atan2f.c: Correct value of pi to be correct
	round-to-nearest value.

	* sysdeps/libm-ieee754/e_log.c: Make sure exceptions are raised.
	* sysdeps/libm-ieee754/e_log10.c: Likewise.
	* sysdeps/libm-ieee754/e_log10f.c: Likewise.
	* sysdeps/libm-ieee754/e_logf.c: Likewise.
	* sysdeps/libm-ieee754/s_log1p.c: Likewise. Also use correct -Inf.
	* sysdeps/libm-ieee754/s_log1pf.c: Likewise. Also use correct -Inf.
	* sysdeps/libm-ieee754/s_log2.c: Likewise.
	* sysdeps/libm-ieee754/s_log2f.c: Likewise.

1997-07-15 21:54  Thorsten Kukuk  <kukuk@vt.uni-paderborn.de>

	* nis/nss_compat/compat-grp.c: Fix "buffer to small" problems
	and memory leaks.
	* nis/nss_compat/compat-pwd.c: Likewise.
	* nis/nss_compat/compat-spwd.c: Likewise.
	* nis/nss_nis/nis-alias.c: Likewise.
	* nis/nss_nis/nis-ethers.c: Likewise.
	* nis/nss_nis/nis-grp.c: Likewise.
	* nis/nss_nis/nis-hosts.c: Likewise.
	* nis/nss_nis/nis-network.c: Likewise.
	* nis/nss_nis/nis-proto.c: Likewise.
	* nis/nss_nis/nis-pwd.c: Likewise.
	* nis/nss_nis/nis-rpc.c: Likewise.
	* nis/nss_nis/nis-service.c: Likewise.
	* nis/nss_nis/nis-spwd.c: Likewise.
	* nis/nss_nisplus-alias.c: Likewise.
	* nis/nss_nisplus-ethers.c: Likewise.
	* nis/nss_nisplus-grp.c: Likewise.
	* nis/nss_nisplus-hosts.c: Likewise.
	* nis/nss_nisplus-netgrp.c: Likewise.
	* nis/nss_nisplus-network.c: Likewise.
	* nis/nss_nisplus-proto.c: Likewise.
	* nis/nss_nisplus-pwd.c: Likewise.
	* nis/nss_nisplus-rpc.c: Likewise.
	* nis/nss_nisplus-service.c: Likewise.
	* nis/nss_nisplus-spwd.c: Likewise.

	* nis/nss_nisplus-parse.c: If buffer to small, give -1 back.

1997-07-20  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/m68k/dl-machine.h (elf_machine_rela): Mention program
	name in warning message.
	* sysdeps/powerpc/dl-machine.h (elf_machine_rela): Likewise.
	* sysdeps/sparc/dl-machine.h (elf_machine_rela): Likewise.
	* sysdeps/sparc64/dl-machine.h (elf_machine_rela): Likewise.

	* sysdeps/i386/dl-machine.h (elf_machine_rel): Print program name
	first.

1997-07-20 19:33  Thorsten Kukuk  <kukuk@vt.uni-paderborn.de>

	* libc.map: Add _null_auth and _seterr_reply.

	* sunrpc/clnt_udp.c (clntudp_call): If xargs is NULL, don't encode it.
Diffstat (limited to 'sysdeps/libm-ieee754')
-rw-r--r--sysdeps/libm-ieee754/e_atan2f.c20
-rw-r--r--sysdeps/libm-ieee754/e_log.c4
-rw-r--r--sysdeps/libm-ieee754/e_log10.c16
-rw-r--r--sysdeps/libm-ieee754/e_log10f.c8
-rw-r--r--sysdeps/libm-ieee754/e_logf.c16
-rw-r--r--sysdeps/libm-ieee754/s_isinf.c5
-rw-r--r--sysdeps/libm-ieee754/s_isinff.c2
-rw-r--r--sysdeps/libm-ieee754/s_log1p.c2
-rw-r--r--sysdeps/libm-ieee754/s_log1pf.c14
-rw-r--r--sysdeps/libm-ieee754/s_log2.c4
-rw-r--r--sysdeps/libm-ieee754/s_log2f.c4
11 files changed, 47 insertions, 48 deletions
diff --git a/sysdeps/libm-ieee754/e_atan2f.c b/sysdeps/libm-ieee754/e_atan2f.c
index 437975f79f..8b3398c0a3 100644
--- a/sysdeps/libm-ieee754/e_atan2f.c
+++ b/sysdeps/libm-ieee754/e_atan2f.c
@@ -8,7 +8,7 @@
  *
  * Developed at SunPro, a Sun Microsystems, Inc. business.
  * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice 
+ * software is freely granted, provided that this notice
  * is preserved.
  * ====================================================
  */
@@ -21,16 +21,16 @@ static char rcsid[] = "$NetBSD: e_atan2f.c,v 1.4 1995/05/10 20:44:53 jtc Exp $";
 #include "math_private.h"
 
 #ifdef __STDC__
-static const float 
+static const float
 #else
-static float 
+static float
 #endif
 tiny  = 1.0e-30,
 zero  = 0.0,
-pi_o_4  = 7.8539818525e-01, /* 0x3f490fdb */
-pi_o_2  = 1.5707963705e+00, /* 0x3fc90fdb */
-pi      = 3.1415925026e+00, /* 0x40490fda */
-pi_lo   = 1.5099578832e-07; /* 0x34222168 */
+pi_o_4  = 7.8539818525e-01,  /* 0x3f490fdb */
+pi_o_2  = 1.5707963705e+00,  /* 0x3fc90fdb */
+pi      = 3.1415927410e+00,  /* 0x40490fdb */
+pi_lo   = -8.7422776573e-07; /* 0xb3bbbd2e */
 
 #ifdef __STDC__
 	float __ieee754_atan2f(float y, float x)
@@ -38,7 +38,7 @@ pi_lo   = 1.5099578832e-07; /* 0x34222168 */
 	float __ieee754_atan2f(y,x)
 	float  y,x;
 #endif
-{  
+{
 	float z;
 	int32_t k,m,hx,hy,ix,iy;
 
@@ -55,7 +55,7 @@ pi_lo   = 1.5099578832e-07; /* 0x34222168 */
     /* when y = 0 */
 	if(iy==0) {
 	    switch(m) {
-		case 0: 
+		case 0:
 		case 1: return y; 	/* atan(+-0,+anything)=+-0 */
 		case 2: return  pi+tiny;/* atan(+0,-anything) = pi */
 		case 3: return -pi-tiny;/* atan(-0,-anything) =-pi */
@@ -63,7 +63,7 @@ pi_lo   = 1.5099578832e-07; /* 0x34222168 */
 	}
     /* when x = 0 */
 	if(ix==0) return (hy<0)?  -pi_o_2-tiny: pi_o_2+tiny;
-	    
+
     /* when x is INF */
 	if(ix==0x7f800000) {
 	    if(iy==0x7f800000) {
diff --git a/sysdeps/libm-ieee754/e_log.c b/sysdeps/libm-ieee754/e_log.c
index f584694686..e4e6eab6c5 100644
--- a/sysdeps/libm-ieee754/e_log.c
+++ b/sysdeps/libm-ieee754/e_log.c
@@ -106,8 +106,8 @@ static double zero   =  0.0;
 	k=0;
 	if (hx < 0x00100000) {			/* x < 2**-1022  */
 	    if (((hx&0x7fffffff)|lx)==0)
-		return -two54/zero;		/* log(+-0)=-inf */
-	    if (hx<0) return (x-x)/zero;	/* log(-#) = NaN */
+		return -two54/(x-x);		/* log(+-0)=-inf */
+	    if (hx<0) return (x-x)/(x-x);	/* log(-#) = NaN */
 	    k -= 54; x *= two54; /* subnormal number, scale up x */
 	    GET_HIGH_WORD(hx,x);
 	}
diff --git a/sysdeps/libm-ieee754/e_log10.c b/sysdeps/libm-ieee754/e_log10.c
index 5d004ac4e2..e8a3278eaf 100644
--- a/sysdeps/libm-ieee754/e_log10.c
+++ b/sysdeps/libm-ieee754/e_log10.c
@@ -5,7 +5,7 @@
  *
  * Developed at SunPro, a Sun Microsystems, Inc. business.
  * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice 
+ * software is freely granted, provided that this notice
  * is preserved.
  * ====================================================
  */
@@ -16,26 +16,26 @@ static char rcsid[] = "$NetBSD: e_log10.c,v 1.9 1995/05/10 20:45:51 jtc Exp $";
 
 /* __ieee754_log10(x)
  * Return the base 10 logarithm of x
- * 
+ *
  * Method :
  *	Let log10_2hi = leading 40 bits of log10(2) and
  *	    log10_2lo = log10(2) - log10_2hi,
  *	    ivln10   = 1/log(10) rounded.
  *	Then
- *		n = ilogb(x), 
+ *		n = ilogb(x),
  *		if(n<0)  n = n+1;
  *		x = scalbn(x,-n);
  *		log10(x) := n*log10_2hi + (n*log10_2lo + ivln10*log(x))
  *
  * Note 1:
- *	To guarantee log10(10**n)=n, where 10**n is normal, the rounding 
+ *	To guarantee log10(10**n)=n, where 10**n is normal, the rounding
  *	mode must set to Round-to-Nearest.
  * Note 2:
  *	[1/log(10)] rounded to 53 bits has error  .198   ulps;
  *	log10 is monotonic at all binary break points.
  *
  * Special cases:
- *	log10(x) is NaN with signal if x < 0; 
+ *	log10(x) is NaN with signal if x < 0;
  *	log10(+INF) is +INF with no signal; log10(0) is -INF with signal;
  *	log10(NaN) is that NaN with no signal;
  *	log10(10**N) = N  for N=0,1,...,22.
@@ -80,10 +80,10 @@ static double zero   =  0.0;
 	EXTRACT_WORDS(hx,lx,x);
 
         k=0;
-        if (hx < 0x00100000) {                  /* x < 2**-1022  */
+        if (hx < 0x00100000) {			/* x < 2**-1022  */
             if (((hx&0x7fffffff)|lx)==0)
-                return -two54/zero;             /* log(+-0)=-inf */
-            if (hx<0) return (x-x)/zero;        /* log(-#) = NaN */
+                return -two54/(x-x);		/* log(+-0)=-inf */
+            if (hx<0) return (x-x)/(x-x);	/* log(-#) = NaN */
             k -= 54; x *= two54; /* subnormal number, scale up x */
 	    GET_HIGH_WORD(hx,x);
         }
diff --git a/sysdeps/libm-ieee754/e_log10f.c b/sysdeps/libm-ieee754/e_log10f.c
index 2082a763bb..cea3d9156b 100644
--- a/sysdeps/libm-ieee754/e_log10f.c
+++ b/sysdeps/libm-ieee754/e_log10f.c
@@ -8,7 +8,7 @@
  *
  * Developed at SunPro, a Sun Microsystems, Inc. business.
  * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice 
+ * software is freely granted, provided that this notice
  * is preserved.
  * ====================================================
  */
@@ -49,10 +49,10 @@ static float zero   =  0.0;
 	GET_FLOAT_WORD(hx,x);
 
         k=0;
-        if (hx < 0x00800000) {                  /* x < 2**-126  */
+        if (hx < 0x00800000) {			/* x < 2**-126  */
             if ((hx&0x7fffffff)==0)
-                return -two25/zero;             /* log(+-0)=-inf */
-            if (hx<0) return (x-x)/zero;        /* log(-#) = NaN */
+                return -two25/(x-x);		/* log(+-0)=-inf */
+            if (hx<0) return (x-x)/(x-x);	/* log(-#) = NaN */
             k -= 25; x *= two25; /* subnormal number, scale up x */
 	    GET_FLOAT_WORD(hx,x);
         }
diff --git a/sysdeps/libm-ieee754/e_logf.c b/sysdeps/libm-ieee754/e_logf.c
index 1481fd01cb..0f1af93ba8 100644
--- a/sysdeps/libm-ieee754/e_logf.c
+++ b/sysdeps/libm-ieee754/e_logf.c
@@ -8,7 +8,7 @@
  *
  * Developed at SunPro, a Sun Microsystems, Inc. business.
  * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice 
+ * software is freely granted, provided that this notice
  * is preserved.
  * ====================================================
  */
@@ -56,12 +56,12 @@ static float zero   =  0.0;
 
 	k=0;
 	if (ix < 0x00800000) {			/* x < 2**-126  */
-	    if ((ix&0x7fffffff)==0) 
-		return -two25/zero;		/* log(+-0)=-inf */
-	    if (ix<0) return (x-x)/zero;	/* log(-#) = NaN */
+	    if ((ix&0x7fffffff)==0)
+		return -two25/(x-x);		/* log(+-0)=-inf */
+	    if (ix<0) return (x-x)/(x-x);	/* log(-#) = NaN */
 	    k -= 25; x *= two25; /* subnormal number, scale up x */
 	    GET_FLOAT_WORD(ix,x);
-	} 
+	}
 	if (ix >= 0x7f800000) return x+x;
 	k += (ix>>23)-127;
 	ix &= 0x007fffff;
@@ -76,14 +76,14 @@ static float zero   =  0.0;
 	    if(k==0) return f-R; else {dk=(float)k;
 	    	     return dk*ln2_hi-((R-dk*ln2_lo)-f);}
 	}
- 	s = f/((float)2.0+f); 
+ 	s = f/((float)2.0+f);
 	dk = (float)k;
 	z = s*s;
 	i = ix-(0x6147a<<3);
 	w = z*z;
 	j = (0x6b851<<3)-ix;
-	t1= w*(Lg2+w*(Lg4+w*Lg6)); 
-	t2= z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7))); 
+	t1= w*(Lg2+w*(Lg4+w*Lg6));
+	t2= z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7)));
 	i |= j;
 	R = t2+t1;
 	if(i>0) {
diff --git a/sysdeps/libm-ieee754/s_isinf.c b/sysdeps/libm-ieee754/s_isinf.c
index d3c2cb55b7..6f76ce1fba 100644
--- a/sysdeps/libm-ieee754/s_isinf.c
+++ b/sysdeps/libm-ieee754/s_isinf.c
@@ -23,12 +23,11 @@ static char rcsid[] = "$NetBSD: s_isinf.c,v 1.3 1995/05/11 23:20:14 jtc Exp $";
 	double x;
 #endif
 {
-	u_int32_t hx;
-	int32_t lx;
+	int32_t hx,lx;
 	EXTRACT_WORDS(hx,lx,x);
 	lx |= (hx & 0x7fffffff) ^ 0x7ff00000;
 	lx |= -lx;
-	return ~(lx >> 31) & (1 - ((hx >> 30) & 2));
+	return ~(lx >> 31) & (hx >> 30);
 }
 weak_alias (__isinf, isinf)
 #ifdef NO_LONG_DOUBLE
diff --git a/sysdeps/libm-ieee754/s_isinff.c b/sysdeps/libm-ieee754/s_isinff.c
index 9acc0df6ec..18a0b5e03b 100644
--- a/sysdeps/libm-ieee754/s_isinff.c
+++ b/sysdeps/libm-ieee754/s_isinff.c
@@ -27,6 +27,6 @@ static char rcsid[] = "$NetBSD: s_isinff.c,v 1.3 1995/05/11 23:20:21 jtc Exp $";
 	t = ix & 0x7fffffff;
 	t ^= 0x7f800000;
 	t |= -t;
-	return ~(t >> 31) & (1 - ((ix & 0x80000000) >> 30));
+	return ~(t >> 31) & (ix >> 30);
 }
 weak_alias (__isinff, isinff)
diff --git a/sysdeps/libm-ieee754/s_log1p.c b/sysdeps/libm-ieee754/s_log1p.c
index cc380a1091..086c0dce6c 100644
--- a/sysdeps/libm-ieee754/s_log1p.c
+++ b/sysdeps/libm-ieee754/s_log1p.c
@@ -120,7 +120,7 @@ static double zero = 0.0;
 	k = 1;
 	if (hx < 0x3FDA827A) {			/* x < 0.41422  */
 	    if(ax>=0x3ff00000) {		/* x <= -1.0 */
-		if(x==-1.0) return -two54/zero; /* log1p(-1)=+inf */
+		if(x==-1.0) return -two54/(x-x);/* log1p(-1)=+inf */
 		else return (x-x)/(x-x);	/* log1p(x<-1)=NaN */
 	    }
 	    if(ax<0x3e200000) {			/* |x| < 2**-29 */
diff --git a/sysdeps/libm-ieee754/s_log1pf.c b/sysdeps/libm-ieee754/s_log1pf.c
index ee0a83958d..5b1237b0d0 100644
--- a/sysdeps/libm-ieee754/s_log1pf.c
+++ b/sysdeps/libm-ieee754/s_log1pf.c
@@ -8,7 +8,7 @@
  *
  * Developed at SunPro, a Sun Microsystems, Inc. business.
  * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice 
+ * software is freely granted, provided that this notice
  * is preserved.
  * ====================================================
  */
@@ -58,7 +58,7 @@ static float zero = 0.0;
 	k = 1;
 	if (hx < 0x3ed413d7) {			/* x < 0.41422  */
 	    if(ax>=0x3f800000) {		/* x <= -1.0 */
-		if(x==(float)-1.0) return -two25/zero; /* log1p(-1)=+inf */
+		if(x==(float)-1.0) return -two25/(x-x); /* log1p(-1)=+inf */
 		else return (x-x)/(x-x);	/* log1p(x<-1)=NaN */
 	    }
 	    if(ax<0x31000000) {			/* |x| < 2**-29 */
@@ -70,11 +70,11 @@ static float zero = 0.0;
 	    }
 	    if(hx>0||hx<=((int32_t)0xbe95f61f)) {
 		k=0;f=x;hu=1;}	/* -0.2929<x<0.41422 */
-	} 
+	}
 	if (hx >= 0x7f800000) return x+x;
 	if(k!=0) {
 	    if(hx<0x5a000000) {
-		u  = (float)1.0+x; 
+		u  = (float)1.0+x;
 		GET_FLOAT_WORD(hu,u);
 	        k  = (hu>>23)-127;
 		/* correction term */
@@ -90,7 +90,7 @@ static float zero = 0.0;
 	    if(hu<0x3504f7) {
 	        SET_FLOAT_WORD(u,hu|0x3f800000);/* normalize u */
 	    } else {
-	        k += 1; 
+	        k += 1;
 		SET_FLOAT_WORD(u,hu|0x3f000000);	/* normalize u/2 */
 	        hu = (0x00800000-hu)>>2;
 	    }
@@ -98,13 +98,13 @@ static float zero = 0.0;
 	}
 	hfsq=(float)0.5*f*f;
 	if(hu==0) {	/* |f| < 2**-20 */
-	    if(f==zero) if(k==0) return zero;  
+	    if(f==zero) if(k==0) return zero;
 			else {c += k*ln2_lo; return k*ln2_hi+c;}
 	    R = hfsq*((float)1.0-(float)0.66666666666666666*f);
 	    if(k==0) return f-R; else
 	    	     return k*ln2_hi-((R-(k*ln2_lo+c))-f);
 	}
- 	s = f/((float)2.0+f); 
+ 	s = f/((float)2.0+f);
 	z = s*s;
 	R = z*(Lp1+z*(Lp2+z*(Lp3+z*(Lp4+z*(Lp5+z*(Lp6+z*Lp7))))));
 	if(k==0) return f-(hfsq-s*(hfsq+R)); else
diff --git a/sysdeps/libm-ieee754/s_log2.c b/sysdeps/libm-ieee754/s_log2.c
index 46b53cfeff..93c20b3db1 100644
--- a/sysdeps/libm-ieee754/s_log2.c
+++ b/sysdeps/libm-ieee754/s_log2.c
@@ -93,8 +93,8 @@ static double zero   =  0.0;
 	k=0;
 	if (hx < 0x00100000) {			/* x < 2**-1022  */
 	    if (((hx&0x7fffffff)|lx)==0)
-		return -two54/zero;		/* log(+-0)=-inf */
-	    if (hx<0) return (x-x)/zero;	/* log(-#) = NaN */
+		return -two54/(x-x);		/* log(+-0)=-inf */
+	    if (hx<0) return (x-x)/(x-x);	/* log(-#) = NaN */
 	    k -= 54; x *= two54; /* subnormal number, scale up x */
 	    GET_HIGH_WORD(hx,x);
 	}
diff --git a/sysdeps/libm-ieee754/s_log2f.c b/sysdeps/libm-ieee754/s_log2f.c
index 6415c37f53..da9dfb8324 100644
--- a/sysdeps/libm-ieee754/s_log2f.c
+++ b/sysdeps/libm-ieee754/s_log2f.c
@@ -53,8 +53,8 @@ static float zero   =  0.0;
 	k=0;
 	if (ix < 0x00800000) {			/* x < 2**-126  */
 	    if ((ix&0x7fffffff)==0)
-		return -two25/zero;		/* log(+-0)=-inf */
-	    if (ix<0) return (x-x)/zero;	/* log(-#) = NaN */
+		return -two25/(x-x);		/* log(+-0)=-inf */
+	    if (ix<0) return (x-x)/(x-x);	/* log(-#) = NaN */
 	    k -= 25; x *= two25; /* subnormal number, scale up x */
 	    GET_FLOAT_WORD(ix,x);
 	}