https://sourceforge.net/tracker/?func=detail&atid=102435&aid=3441135&group_id=2435
https://bugs.gentoo.org/395893

????-??-??  Keith Marshall  <keithmarshall@...>

	Support pragmatic identification for w32api source directory.

	* aclocal.m4 (MINGW_AC_W32API_SRCDIR): New macro; implement it.
	* configure.in (W32API_INCLUDE): Assign using MINGW_AC_W32API_SRCDIR.
	* Makefile.in (W32API_INCLUDE): Prefix -I flag to AC_SUBST value.
	* mingwex/Makefile.in (W32API_INCLUDE): Likewise.
	* profile/Makefile.in (W32API_INCLUDE): Likewise.

diff -r 62c176864807 Makefile.in
--- a/Makefile.in	Mon Nov 28 11:32:25 2011 +0000
+++ b/Makefile.in	Mon Nov 28 21:18:55 2011 +0000
@@ -166,9 +166,9 @@ THREAD_DLL_NAME = $(THREAD_DLL)$(THREAD_
 # Various libraries.
 LIBM_A=@LIBM_A@
 
-W32API_INCLUDE = @W32API_INCLUDE@
-INCLUDES = -I$(srcdir)/include \
-  -I$(srcdir)/../include \
+W32API_INCLUDE = -I @W32API_INCLUDE@
+INCLUDES = -I $(srcdir)/include \
+  -I $(srcdir)/../include \
   -nostdinc \
   -iwithprefixbefore include
 ALL_CFLAGS = $(CFLAGS) $(INCLUDES) $(W32API_INCLUDE)
diff -r 62c176864807 aclocal.m4
--- a/aclocal.m4	Mon Nov 28 11:32:25 2011 +0000
+++ b/aclocal.m4	Mon Nov 28 21:18:55 2011 +0000
@@ -15,7 +15,65 @@ AC_DEFUN([MINGW_AC_CONFIG_SRCDIR],
  AC_MSG_CHECKING([package version])
  PACKAGE_VERSION=`awk '$[2] == "'"$1"'" { print $[3] }' ${srcdir}/$2`
  AC_MSG_RESULT([$PACKAGE_VERSION])dnl
-]) #MINGW_AC_CONFIG_SRCDIR
+])# MINGW_AC_CONFIG_SRCDIR
+
+# MINGW_AC_W32API_SRCDIR
+# ----------------------
+# Attempt to identify the location of the w32api sources.
+# Accept an explicit location specified by to user, as argument
+# to --with-w32api-srcdir; if unspecified, fall back to standard
+# location relative to ${srcdir}.  Identification requires that
+# include/windows.h is present within the nominated directory.
+# This is naive, but AC_CHECK_HEADER cannot be used because
+# the system's w32api headers will interfere.
+#
+AC_DEFUN([MINGW_AC_W32API_SRCDIR],
+[AC_ARG_WITH([w32api-srcdir],
+ [AS_HELP_STRING([--with-w32api-srcdir=DIR],
+  [locate w32api sources in DIR [SRCDIR/../w32api]])
+ ],[],[with_w32api_srcdir=NONE])
+ AS_IF([test "x${with_w32api_srcdir}" = xNONE],
+ [AC_MSG_CHECKING([include path for w32api headers])
+  for with_w32api_srcdir in ${srcdir}/../w32api*; do
+    test -f "${with_w32api_srcdir}/include/windows.h" && break
+    with_w32api_srcdir=NONE
+  done
+  AS_IF([test "x${with_w32api_srcdir}" = xNONE],
+  [AC_MSG_RESULT([none found])
+   AC_MSG_RESULT
+   AC_MSG_WARN([source directory containing include/windows.h not found])
+   AC_MSG_WARN([ensure w32api sources are installed at \${top_srcdir}/../w32api*])
+   AC_MSG_WARN([or use --with-w32api-srcdir=DIR to specify an alternative])
+  ],
+  [case "${with_w32api_srcdir}" in
+     "${srcdir}/"*) with_w32api_srcdir="`echo "${with_w32api_srcdir}"dnl
+       | sed s,"^${srcdir}/",'${top_srcdir}/',`" ;;
+   esac
+   AC_MSG_RESULT([${with_w32api_srcdir}/include])
+  ])
+ ],
+ [AC_MSG_CHECKING([for windows.h in ${with_w32api_srcdir}/include])
+  AS_IF([test -f "${with_w32api_srcdir}/include/windows.h"],
+  [AC_MSG_RESULT([yes])
+   case "${with_w32api_srcdir}" in /*) ;;
+     *) with_w32api_srcdir='${top_builddir}/'"${with_w32api_srcdir}" ;;
+   esac
+  ],
+  [AC_MSG_RESULT([no])
+   AC_MSG_RESULT
+   AC_MSG_WARN([the nominated directory, ${with_w32api_srcdir}])
+   AC_MSG_WARN([does not appear to contain valid w32api source code])
+   AC_MSG_WARN([(file '${with_w32api_srcdir}/include/windows.h' is not present)])
+   with_w32api_srcdir=NONE
+  ])
+ ])
+ AS_IF([test "x${with_w32api_srcdir}" = xNONE],
+ [AC_MSG_WARN([please correct this omission and run configure again])
+  AC_MSG_RESULT
+  AC_MSG_ERROR([unable to continue until this issue is resolved])
+ ])
+ W32API_INCLUDE="${with_w32api_srcdir}/include"
+])# MINGW_AC_W32API_SRCDIR
 
 # The following is copied from `no-executables.m4', in the top
 # `src/config' directory.
diff -r 62c176864807 configure.in
--- a/configure.in	Mon Nov 28 11:32:25 2011 +0000
+++ b/configure.in	Mon Nov 28 21:18:55 2011 +0000
@@ -44,7 +44,7 @@ AC_CHECK_TOOL([WINDRES], [windres], [win
 
 AC_SUBST([NO_CYGWIN])
 AC_SUBST([HEADER_SUBDIR])
-AC_SUBST([W32API_INCLUDE], ['-I ${top_srcdir}/../w32api/include'])
+AC_SUBST([W32API_INCLUDE], [MINGW_AC_W32API_SRCDIR])
 
 # The following are used by the GCC profiling hooks...
 #
diff -r 62c176864807 mingwex/Makefile.in
--- a/mingwex/Makefile.in	Mon Nov 28 11:32:25 2011 +0000
+++ b/mingwex/Makefile.in	Mon Nov 28 21:18:55 2011 +0000
@@ -126,10 +126,9 @@ ifdef NO_CYGWIN
 override CC := ${NO_CYGWIN} $(firstword $(filter-out ${NO_CYGWIN},${CC}))
 endif
 
-W32API_INCLUDE = @W32API_INCLUDE@
-INCLUDES = -I${srcdir} -I${top_srcdir} -I${top_srcdir}/include \
-  -nostdinc \
-  -iwithprefixbefore include
+W32API_INCLUDE = -I @W32API_INCLUDE@
+INCLUDES = -I ${srcdir} -I ${top_srcdir} -I ${top_srcdir}/include \
+  -nostdinc -isystem @W32API_INCLUDE@ -iwithprefixbefore include
 ALL_CFLAGS = $(CFLAGS) $(WARNFLAGS) $(OPTFLAGS) $(INCLUDES) $(W32API_INCLUDE)
 ALL_CXXFLAGS = $(CXXFLAGS) $(WARNFLAGS) $(OPTFLAGS) $(INCLUDES) -nostdinc++ $(W32API_INCLUDE)
 
diff -r 62c176864807 profile/Makefile.in
--- a/profile/Makefile.in	Mon Nov 28 11:32:25 2011 +0000
+++ b/profile/Makefile.in	Mon Nov 28 21:18:55 2011 +0000
@@ -65,10 +65,9 @@ THREAD_DLL = @THREAD_DLL@
 THREAD_DLL_VERSION = 10
 THREAD_DLL_NAME = $(THREAD_DLL)$(THREAD_DLL_VERSION).dll
 
-W32API_INCLUDE = @W32API_INCLUDE@
-INCLUDES = -I${srcdir} -I${top_srcdir}/include \
-  -nostdinc \
-  -iwithprefixbefore include
+W32API_INCLUDE = -I @W32API_INCLUDE@
+INCLUDES = -I ${srcdir} -I ${top_srcdir}/include \
+  -nostdinc -iwithprefixbefore include
 ALL_CFLAGS = $(CFLAGS) $(INCLUDES) $(W32API_INCLUDE)
 ALL_CXXFLAGS = $(CXXFLAGS) $(INCLUDES) -nostdinc++ $(W32API_INCLUDE)