[libdfp-patches] Correct placement of __STDC_WANT_DEC_FP__ guard in dfp/math.h

[Ryan Arnold <rsa@xxxxxxxxxx>]

I've added the following patches to libdfp upstream:

2010-11-29  Ryan S. Arnold  <rsa@xxxxxxxxxx>

        * README.user: Added clarification of how to include dfp/stdlib.h,
        dfp/fenv.h and dfp/wchar.h.

2010-11-29  Ryan S. Arnold  <rsa@xxxxxxxxxx>

        * README.user: Added clarification of how to include dfp/math.h.

2010-11-29  Ryan S. Arnold  <rsa@xxxxxxxxxx>

        * dfp/math.h: Move #include_next <math.h> so that if the compiler
        invocation has -I/<path>/include/dfp/ but doesn't define
        __STDC_WANT_DEC_FP__ that they still get the system math.h.

There was a problem such that if -I/usr/include/dfp/ was prepended to
the search order but __STDC_WANT_DEC_FP was not defined then #include
<math.h> would pick up /usr/include/dfp/math.h but fail to
include /usr/include/math.h because of a misplaced #ifdef
__STDC_WANT_DEC_FP__ guard.

I've also updated the documentation on how to properly include the
Libdfp header files which override the system headers files, e.g.
stdlib.h, math.h, fenv.h, and wchar.h.

Signed-off-by: Ryan S. Arnold  <rsa@xxxxxxxxxx>



Index: ChangeLog
===================================================================
--- ChangeLog	(revision 12162)
+++ ChangeLog	(revision 12163)
@@ -1,3 +1,9 @@
+2010-11-29  Ryan S. Arnold  <rsa@xxxxxxxxxx>
+
+	* dfp/math.h: Move #include_next <math.h> so that if the compiler
+	invocation has -I/<path>/include/dfp/ but doesn't define
+	__STDC_WANT_DEC_FP__ that they still get the system math.h.
+
 2010-11-19  Ryan S. Arnold  <rsa@xxxxxxxxxx>
 
 	* CONTRIBUTORS: Added Luis Machado.  Added DCO requirements.
Index: dfp/math.h
===================================================================
--- dfp/math.h	(revision 12162)
+++ dfp/math.h	(revision 12163)
@@ -2,7 +2,7 @@
    system math.h classification macros.
 
    Copyright (C) 2006 IBM Corporation.
-   Copyright (C) 2009 Free Software Foundation, Inc.
+   Copyright (C) 2009, 2010 Free Software Foundation, Inc.
 
    This file is part of the Decimal Floating Point C Library.
 
@@ -31,12 +31,15 @@
 # error "dfp/<math.h> should be included before the system math.h."
 #endif
 
-#ifdef __STDC_WANT_DEC_FP__
-
 /* Include the system math.h first so that we can undef and redefine the
  * classification functions to select for _Decimal[32|64|128] types.  */
 #include_next <math.h>
 
+/* Include this after the #include_next <math.h> so that if the user has
+ * -I/<path>/include/dfp/ on their compilation line but doesn't define
+ *  __STDC_WANT_DEC_FPP that they still get the system math.h.  */
+#ifdef __STDC_WANT_DEC_FP__
+
 #include <features.h>
 __BEGIN_DECLS
Index: README.user
===================================================================
--- README.user	(revision 12163)
+++ README.user	(revision 12164)
@@ -247,6 +247,16 @@
 This mechanism allows Libdfp to add the Decimal interfaces required by the
 specification to the aforementioned headers.
 
+In order to pick up the Libdfp math.h prototypes and classification macro
+overrides compile with the following:
+
+-I/pathto/include/dfp/ -D__STDC_WANT_DEC_FP__
+
+And then in the application source simply using the following include will
+pick up both /pathto/include/dfp/math.h and /usr/include/math.h:
+
+#include <math.h>
+
 ---------------------------------------------------------------------------
 7.  Compile and Link
 
Index: ChangeLog
===================================================================
--- ChangeLog	(revision 12163)
+++ ChangeLog	(revision 12164)
@@ -1,5 +1,9 @@
 2010-11-29  Ryan S. Arnold  <rsa@xxxxxxxxxx>
 
+	* README.user: Added clarification of how to include dfp/math.h.
+
+2010-11-29  Ryan S. Arnold  <rsa@xxxxxxxxxx>
+
 	* dfp/math.h: Move #include_next <math.h> so that if the compiler
 	invocation has -I/<path>/include/dfp/ but doesn't define
 	__STDC_WANT_DEC_FP__ that they still get the system math.h.
Index: README.user
===================================================================
--- README.user	(revision 12164)
+++ README.user	(working copy)
@@ -247,15 +247,18 @@
 This mechanism allows Libdfp to add the Decimal interfaces required by the
 specification to the aforementioned headers.
 
-In order to pick up the Libdfp math.h prototypes and classification macro
+In order to pick up the Libdfp prototypes and classification macro
 overrides compile with the following:
 
 -I/pathto/include/dfp/ -D__STDC_WANT_DEC_FP__
 
 And then in the application source simply using the following include will
-pick up both /pathto/include/dfp/math.h and /usr/include/math.h:
+pick up both /pathto/include/dfp/<foo>.h and /usr/include/<foo>.h:
 
 #include <math.h>
+#include <fenv.h>
+#include <stdlib.h>
+#include <wchar.h>
 
 ---------------------------------------------------------------------------
 7.  Compile and Link
Index: ChangeLog
===================================================================
--- ChangeLog	(revision 12164)
+++ ChangeLog	(working copy)
@@ -1,5 +1,10 @@
 2010-11-29  Ryan S. Arnold  <rsa@xxxxxxxxxx>
 
+	* README.user: Added clarification of how to include dfp/stdlib.h,
+	dfp/fenv.h and dfp/wchar.h.
+
+2010-11-29  Ryan S. Arnold  <rsa@xxxxxxxxxx>
+
 	* README.user: Added clarification of how to include dfp/math.h.
 
 2010-11-29  Ryan S. Arnold  <rsa@xxxxxxxxxx>