libphobos: Fix configure test for backtrace-supported.h

libphobos/ChangeLog:

2019-04-16  Iain Buclaw  <ibuclaw@gdcproject.org>

	* config.h.in: Regenerate.
	* configure: Regenerate.
	* m4/druntime/libraries.m4 (DRUNTIME_LIBRARIES_BACKTRACE): Set
	CPPFLAGS correctly for backtrace support test.

From-SVN: r270377

libphobos/ChangeLog

+2019-04-16  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* config.h.in: Regenerate.
+	* configure: Regenerate.
+	* m4/druntime/libraries.m4 (DRUNTIME_LIBRARIES_BACKTRACE): Set
+	CPPFLAGS correctly for backtrace support test.
+
 2019-04-14  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	* configure.tgt (LIBPHOBOS_SUPPORTED): Default to no.

libphobos/config.h.in

@@ -54,3 +54,35 @@
 
 /* Define to 1 if you have the ANSI C header files. */
 #undef STDC_HEADERS
+
+/* Enable extensions on AIX 3, Interix.  */
+#ifndef _ALL_SOURCE
+# undef _ALL_SOURCE
+#endif
+/* Enable GNU extensions on systems that have them.  */
+#ifndef _GNU_SOURCE
+# undef _GNU_SOURCE
+#endif
+/* Enable threading extensions on Solaris.  */
+#ifndef _POSIX_PTHREAD_SEMANTICS
+# undef _POSIX_PTHREAD_SEMANTICS
+#endif
+/* Enable extensions on HP NonStop.  */
+#ifndef _TANDEM_SOURCE
+# undef _TANDEM_SOURCE
+#endif
+/* Enable general extensions on Solaris.  */
+#ifndef __EXTENSIONS__
+# undef __EXTENSIONS__
+#endif
+
+
+/* Define to 1 if on MINIX. */
+#undef _MINIX
+
+/* Define to 2 if the system does not provide POSIX.1 features except with
+   this defined. */
+#undef _POSIX_1_SOURCE
+
+/* Define to 1 if you need to in order for `stat' and other things to work. */
+#undef _POSIX_SOURCE

libphobos/configure

@@ -14838,7 +14838,7 @@ fi
     LIBBACKTRACE=../../libbacktrace/libbacktrace.la
 
     gdc_save_CPPFLAGS=$CPPFLAGS
-    CPPFLAGS+=" -I../libbacktrace "
+    CPPFLAGS="$CPPFLAGS -I../libbacktrace "
 
     ac_fn_c_check_header_mongrel "$LINENO" "backtrace-supported.h" "ac_cv_header_backtrace_supported_h" "$ac_includes_default"
 if test "x$ac_cv_header_backtrace_supported_h" = xyes; then :

libphobos/m4/druntime/libraries.m4

@@ -178,7 +178,7 @@ AC_DEFUN([DRUNTIME_LIBRARIES_BACKTRACE],
     LIBBACKTRACE=../../libbacktrace/libbacktrace.la
 
     gdc_save_CPPFLAGS=$CPPFLAGS
-    CPPFLAGS+=" -I../libbacktrace "
+    CPPFLAGS="$CPPFLAGS -I../libbacktrace "
 
     AC_CHECK_HEADER(backtrace-supported.h, have_libbacktrace_h=true,
       have_libbacktrace_h=false)