>From cf308efdb00585d5e7139c0e6eff3ad4854769a1 Mon Sep 17 00:00:00 2001
From: Bruno Haible <address@hidden>
Date: Sat, 17 Dec 2016 19:26:04 +0100
Subject: [PATCH 04/20] atan2f: Avoid redefinition error on MSVC.

* m4/math_h.m4 (gl_MATH_H_DEFAULTS): Define REPLACE_ATAN2F.
* m4/atan2f.m4 (gl_FUNC_ATAN2F): Set REPLACE_ATAN2F to 1 if the function
may be defined as an inline function.
* modules/math (Makefile.am): Substitute REPLACE_ATAN2F.
* lib/math.in.h (atan2f): Override if REPLACE_ATAN2F is 1.
---
 ChangeLog     |  9 +++++++++
 lib/math.in.h | 15 ++++++++++++---
 m4/atan2f.m4  |  6 +++++-
 m4/math_h.m4  |  1 +
 modules/math  |  1 +
 5 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index b03ae87..afac64d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,14 @@
 2016-12-17  Bruno Haible  <address@hidden>
 
+	atan2f: Avoid redefinition error on MSVC.
+	* m4/math_h.m4 (gl_MATH_H_DEFAULTS): Define REPLACE_ATAN2F.
+	* m4/atan2f.m4 (gl_FUNC_ATAN2F): Set REPLACE_ATAN2F to 1 if the function
+	may be defined as an inline function.
+	* modules/math (Makefile.am): Substitute REPLACE_ATAN2F.
+	* lib/math.in.h (atan2f): Override if REPLACE_ATAN2F is 1.
+
+2016-12-17  Bruno Haible  <address@hidden>
+
 	atanf: Avoid redefinition error on MSVC.
 	* m4/math_h.m4 (gl_MATH_H_DEFAULTS): Define REPLACE_ATANF.
 	* m4/atanf.m4 (gl_FUNC_ATANF): Set REPLACE_ATANF to 1 if the function
diff --git a/lib/math.in.h b/lib/math.in.h
index 04bbd4e..9d28a43 100644
--- a/lib/math.in.h
+++ b/lib/math.in.h
@@ -332,11 +332,20 @@ _GL_WARN_ON_USE (atanl, "atanl is unportable - "
 
 
 #if @GNULIB_ATAN2F@
-# if address@hidden@
-#  undef atan2f
+# if @REPLACE_ATAN2F@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef atan2f
+#   define atan2f rpl_atan2f
+#  endif
+_GL_FUNCDECL_RPL (atan2f, float, (float y, float x));
+_GL_CXXALIAS_RPL (atan2f, float, (float y, float x));
+# else
+#  if address@hidden@
+#   undef atan2f
 _GL_FUNCDECL_SYS (atan2f, float, (float y, float x));
-# endif
+#  endif
 _GL_CXXALIAS_SYS (atan2f, float, (float y, float x));
+# endif
 _GL_CXXALIASWARN (atan2f);
 #elif defined GNULIB_POSIXCHECK
 # undef atan2f
diff --git a/m4/atan2f.m4 b/m4/atan2f.m4
index c29f4cb..2788bf8 100644
--- a/m4/atan2f.m4
+++ b/m4/atan2f.m4
@@ -1,4 +1,4 @@
-# atan2f.m4 serial 2
+# atan2f.m4 serial 3
 dnl Copyright (C) 2011-2016 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -22,6 +22,10 @@ AC_DEFUN([gl_FUNC_ATAN2F],
     ATAN2F_LIBM="$ATAN2_LIBM"
   else
     HAVE_ATAN2F=0
+    dnl If the function is declared but does not appear to exist, it may be
+    dnl defined as an inline function. In order to avoid a conflict, we have
+    dnl to define rpl_atan2f, not atan2f.
+    AC_CHECK_DECLS([atan2f], [REPLACE_ATAN2F=1], , [[#include <math.h>]])
     ATAN2F_LIBM="$ATAN2_LIBM"
   fi
   AC_SUBST([ATAN2F_LIBM])
diff --git a/m4/math_h.m4 b/m4/math_h.m4
index 7b2aa5a..ec88b2a 100644
--- a/m4/math_h.m4
+++ b/m4/math_h.m4
@@ -259,6 +259,7 @@ AC_DEFUN([gl_MATH_H_DEFAULTS],
   REPLACE_ACOSF=0;             AC_SUBST([REPLACE_ACOSF])
   REPLACE_ASINF=0;             AC_SUBST([REPLACE_ASINF])
   REPLACE_ATANF=0;             AC_SUBST([REPLACE_ATANF])
+  REPLACE_ATAN2F=0;            AC_SUBST([REPLACE_ATAN2F])
   REPLACE_CBRTF=0;             AC_SUBST([REPLACE_CBRTF])
   REPLACE_CBRTL=0;             AC_SUBST([REPLACE_CBRTL])
   REPLACE_CEIL=0;              AC_SUBST([REPLACE_CEIL])
diff --git a/modules/math b/modules/math
index bc8bc7b..a9de898 100644
--- a/modules/math
+++ b/modules/math
@@ -228,6 +228,7 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	  sed -e 's|@''REPLACE_ACOSF''@|$(REPLACE_ACOSF)|g' \
 	      -e 's|@''REPLACE_ASINF''@|$(REPLACE_ASINF)|g' \
 	      -e 's|@''REPLACE_ATANF''@|$(REPLACE_ATANF)|g' \
+	      -e 's|@''REPLACE_ATAN2F''@|$(REPLACE_ATAN2F)|g' \
 	      -e 's|@''REPLACE_CBRTF''@|$(REPLACE_CBRTF)|g' \
 	      -e 's|@''REPLACE_CBRTL''@|$(REPLACE_CBRTL)|g' \
 	      -e 's|@''REPLACE_CEIL''@|$(REPLACE_CEIL)|g' \
-- 
2.6.4