Fix math.h comment about bits/mathdef.h.

math.h has a comment about definitions from <bits/mathdef.h>.  This
comment is in the wrong place in math.h, far below the inclusion of
<bits/mathdef.h>.  It was originally above the inclusion, but the
inclusion was moved by

1998-11-05  Ulrich Drepper  <drepper@cygnus.com>

        * math/math.h: Unconditionally include bits/mathdef.h.  Declare
        long double functions only if __NO_LONG_DOUBLE_MATH is not
        defined.
        [...]

without moving the comment.  Furthermore, the comment refers
incorrectly to FLT_EVAL_METHOD and DECIMAL_DIG, which are actually
<float.h> macros, and INFINITY, which is in <bits/inf.h>.

This patch moves the comment back above the include it refers to and
removes the description of macros not defined by the header.

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).

	* math/math.h: Move comment about <bits/mathdef.h> definitions
	above inclusion of <bits/mathdef.h>.  Do not mention
	FLT_EVAL_METHOD, INFINITY or DECIMAL_DIG in that comment.

2 files changed, 27 insertions, 34 deletions

diff --git a/ChangeLog b/ChangeLog
index 205da062e6..2026447e98 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2016-08-05  Joseph Myers  <joseph@codesourcery.com>
+
+	* math/math.h: Move comment about <bits/mathdef.h> definitions
+	above inclusion of <bits/mathdef.h>.  Do not mention
+	FLT_EVAL_METHOD, INFINITY or DECIMAL_DIG in that comment.
+
 2016-08-05  Torvald Riegel  <triegel@redhat.com>
 
 	* include/atomic.h (atomic_exchange_relaxed): New.
diff --git a/math/math.h b/math/math.h
index ff9d70adf5..2f77deec87 100644
--- a/math/math.h
+++ b/math/math.h
@@ -45,7 +45,27 @@ __BEGIN_DECLS
 # include <bits/nan.h>
 #endif /* __USE_ISOC99 */
 
-/* Get general and ISO C99 specific information.  */
+/* Get the architecture specific values describing the floating-point
+   evaluation.  The following symbols will get defined:
+
+    float_t	floating-point type at least as wide as `float' used
+		to evaluate `float' expressions
+    double_t	floating-point type at least as wide as `double' used
+		to evaluate `double' expressions
+
+    FP_FAST_FMA
+    FP_FAST_FMAF
+    FP_FAST_FMAL
+		If defined it indicates that the `fma' function
+		generally executes about as fast as a multiply and an add.
+		This macro is defined only iff the `fma' function is
+		implemented directly with a hardware multiply-add instructions.
+
+    FP_ILOGB0	Expands to a value returned by `ilogb (0.0)'.
+    FP_ILOGBNAN	Expands to a value returned by `ilogb (NAN)'.
+
+*/
+
 #include <bits/mathdef.h>
 
 /* The file <bits/mathcalls.h> contains the prototypes for all the
@@ -173,39 +193,6 @@ extern int signgam;
 /* ISO C99 defines some generic macros which work on any data type.  */
 #ifdef __USE_ISOC99
 
-/* Get the architecture specific values describing the floating-point
-   evaluation.  The following symbols will get defined:
-
-    float_t	floating-point type at least as wide as `float' used
-		to evaluate `float' expressions
-    double_t	floating-point type at least as wide as `double' used
-		to evaluate `double' expressions
-
-    FLT_EVAL_METHOD
-		Defined to
-		  0	if `float_t' is `float' and `double_t' is `double'
-		  1	if `float_t' and `double_t' are `double'
-		  2	if `float_t' and `double_t' are `long double'
-		  else	`float_t' and `double_t' are unspecified
-
-    INFINITY	representation of the infinity value of type `float'
-
-    FP_FAST_FMA
-    FP_FAST_FMAF
-    FP_FAST_FMAL
-		If defined it indicates that the `fma' function
-		generally executes about as fast as a multiply and an add.
-		This macro is defined only iff the `fma' function is
-		implemented directly with a hardware multiply-add instructions.
-
-    FP_ILOGB0	Expands to a value returned by `ilogb (0.0)'.
-    FP_ILOGBNAN	Expands to a value returned by `ilogb (NAN)'.
-
-    DECIMAL_DIG	Number of decimal digits supported by conversion between
-		decimal and all internal floating-point formats.
-
-*/
-
 /* All floating-point numbers can be put in one of these categories.  */
 enum
   {