math: update isinf/isnan function comments after move to math.h

Signed-off-by: Yaakov Selkowitz <yselkowi@redhat.com>

newlib/libc/include/math.h

@@ -228,7 +228,7 @@ extern int __signbitd (double x);
  *       supporting multiple floating point types.  Thus, they are
  *       now defined as macros.  Implementations of the old functions
  *       taking double arguments still exist for compatibility purposes
- *       (prototypes for them are in <ieeefp.h>).  */
+ *       (prototypes for them are earlier in this header).  */
 
 #if __GNUC_PREREQ (4, 4)
   #define fpclassify(__x) (__builtin_fpclassify (FP_NAN, FP_INFINITE, \

newlib/libm/common/s_isinf.c

@@ -4,9 +4,8 @@
  *
  * isinf is a <math.h> macro in the C99 standard.  It was previously
  * implemented as a function by newlib and is declared as such in
- * <ieeefp.h>.  Newlib supplies it here as a function if the user
+ * <math.h>.  Newlib supplies it here as a function if the user
- * chooses to use <ieeefp.h> or needs to link older code compiled with the
+ * chooses to use it instead of the C99 macro.
- * previous <math.h> declaration.
  */
 
 #include "fdlibm.h"

newlib/libm/common/s_isnan.c

@@ -53,7 +53,7 @@ ANSI_SYNOPSIS
 	int isnormal(real-floating <[x]>);
 
 	[Archaic SUSv2 functions:]
-	#include <ieeefp.h>
+	#include <math.h>
 	int isnan(double <[arg]>);
 	int isinf(double <[arg]>);
 	int finite(double <[arg]>);
@@ -142,7 +142,7 @@ o-
 	and <<isinf>> are macros that operate on multiple types of
 	floating-point.  The SUSv2 standard declares <<isnan>> as
 	a function taking double.  Newlib has decided to declare
-	them both as macros in math.h and as functions in ieeefp.h to
+	them both as functions and as macros in math.h to
 	maintain backward compatibility.
 
 RETURNS
@@ -154,9 +154,11 @@ The isnan macro returns nonzero if <[x]> is an NaN, else 0.@*
 The isnormal macro returns nonzero if <[x]> has a normal value, else 0.
 
 PORTABILITY
-math.h macros are C99, POSIX.
+math.h macros are C99, POSIX.1-2001.
 
-ieeefp.h funtions are outdated and should be avoided.
+The functions originate from BSD; isnan was listed in the X/Open
+Portability Guide and Single Unix Specification, but was dropped when
+the macro was standardized in POSIX.1-2001.
 
 QUICKREF
 	isnan - pure
@@ -179,8 +181,8 @@ QUICKREF
  * The C99 standard dictates that isnan is a macro taking
  * multiple floating-point types while the SUSv2 standard
  * notes it is a function taking a double argument.  Newlib
- * has chosen to implement it as a macro in <math.h> and
+ * has chosen to declare it both as a function and as a macro in
- * declare it as a function in <ieeefp.h>.
+ * <math.h> for compatibility.
  */
 
 #include "fdlibm.h"

newlib/libm/common/s_isnand.c

@@ -28,7 +28,7 @@ INDEX
 	finitef
 
 ANSI_SYNOPSIS
-	#include <ieeefp.h>
+	#include <math.h>
 	int isnan(double <[arg]>);
 	int isinf(double <[arg]>);
 	int finite(double <[arg]>);
@@ -37,7 +37,7 @@ ANSI_SYNOPSIS
 	int finitef(float <[arg]>);
 
 TRAD_SYNOPSIS
-	#include <ieeefp.h>
+	#include <math.h>
 	int isnan(<[arg]>)
 	double <[arg]>;
 	int isinf(<[arg]>)
@@ -77,8 +77,8 @@ DESCRIPTION
 
 	Note that by the C99 standard, <<isnan>> and <<isinf>> are macros
 	taking any type of floating-point and are declared in
-	<<math.h>>.  Newlib has chosen to declare these as macros in
+	<<math.h>>.  Newlib has chosen to declare these both as functions
-	<<math.h>> and as functions in <<ieeefp.h>>.
+	and as macros in <<math.h>>.
 	
 	The <<isnanf>>, <<isinff>> and <<finitef>> functions perform the same
 	operations as their <<isnan>>, <<isinf>> and <<finite>>

newlib/libm/common/sf_isinf.c

@@ -3,9 +3,8 @@
  *
  * isinf is a <math.h> macro in the C99 standard.  It was previously
  * implemented as isinf and isinff functions by newlib and are still declared
- * as such in <ieeefp.h>.  Newlib supplies it here as a function if the user
+ * as such in <math.h>.  Newlib supplies it here as a function if the user
- * chooses to use <ieeefp.h> or needs to link older code compiled with the
+ * chooses to use it instead of the C99 macro.
- * previous <math.h> declaration.
  */
 
 #include "fdlibm.h"

newlib/libm/common/sf_isnan.c

@@ -15,7 +15,7 @@
 /*
  * isnanf(x) returns 1 is x is nan, else 0;
  *
- * isnanf is an extension declared in <ieeefp.h>.
+ * isnanf is an extension declared in <math.h>.
  */
 
 #include "fdlibm.h"

newlib/libm/machine/spu/sf_isinf.c

@@ -34,7 +34,7 @@
 /*
  * On the SPU isinff(x) always returns 0.
  *
- * isinff is an extension declared in <ieeefp.h>.
+ * isinff is an extension declared in <math.h>.
  */
 int
 isinff (float x)