From 46398941e45b6fd67efb70ee27e5693d8686a4f8 Mon Sep 17 00:00:00 2001
From: Craig Davison <craig65535@gmail.com>
Date: Thu, 11 Aug 2016 21:37:13 -0600
Subject: [PATCH] configure: make the cpp -P detection not clobber CPPFLAGS

CPPPFLAGS is now CPPPFLAG. Fixes CURL_CHECK_DEF.

Fixes #958
---
 acinclude.m4 | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/acinclude.m4 b/acinclude.m4
index fa621b5bda..312efcb473 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -32,8 +32,8 @@ dnl actually be a single double-quoted string concatenating all them.
 AC_DEFUN([CURL_CHECK_DEF], [
   AC_REQUIRE([CURL_CPP_P])dnl
   OLDCPPFLAGS=$CPPFLAGS
-  # CPPPFLAGS comes from CURL_CPP_P
-  CPPFLAGS="$CPPPFLAGS"
+  # CPPPFLAG comes from CURL_CPP_P
+  CPPFLAGS="$CPPFLAGS $CPPPFLAG"
   AS_VAR_PUSHDEF([ac_HaveDef], [curl_cv_have_def_$1])dnl
   AS_VAR_PUSHDEF([ac_Def], [curl_cv_def_$1])dnl
   if test -z "$SED"; then
@@ -3187,12 +3187,15 @@ TEST EINVAL TEST
     if test "x$cpp_p" = "xno"; then
       AC_MSG_WARN([failed to figure out cpp -P alternative])
       # without -P
-      CPPPFLAGS=$OLDCPPFLAGS
+      CPPPFLAG=""
     else
       # with -P
-      CPPPFLAGS=$CPPFLAGS
+      CPPPFLAG="-P"
     fi
     dnl restore CPPFLAGS
     CPPFLAGS=$OLDCPPFLAGS
+  else
+    # without -P
+    CPPPFLAG=""
   fi
 ])