[master] daf9b1979 fix curses autoconf when configured via pkg-config

[Nils Goroll]

commit daf9b1979a3844f3a5be3841bb5342f3372748bc
Author: Nils Goroll <nils.goroll at uplex.de>
Date:   Thu Dec 3 16:55:50 2020 +0100

    fix curses autoconf when configured via pkg-config

diff --git a/bin/varnishhist/Makefile.am b/bin/varnishhist/Makefile.am
index 9fa07e569..79e681d8c 100644
--- a/bin/varnishhist/Makefile.am
+++ b/bin/varnishhist/Makefile.am
@@ -2,7 +2,8 @@
 
 AM_CPPFLAGS = \
 	-I$(top_srcdir)/include \
-	-I$(top_builddir)/include
+	-I$(top_builddir)/include \
+	@CURSES_CFLAGS@
 
 bin_PROGRAMS = varnishhist
 
diff --git a/bin/varnishstat/Makefile.am b/bin/varnishstat/Makefile.am
index a6bc3eed9..94ad656aa 100644
--- a/bin/varnishstat/Makefile.am
+++ b/bin/varnishstat/Makefile.am
@@ -2,7 +2,8 @@
 
 AM_CPPFLAGS = \
 	-I$(top_srcdir)/include \
-	-I$(top_builddir)/include
+	-I$(top_builddir)/include \
+	@CURSES_CFLAGS@
 
 bin_PROGRAMS = varnishstat varnishstat_help_gen
 
diff --git a/bin/varnishtop/Makefile.am b/bin/varnishtop/Makefile.am
index d26fd038f..cdb63b5f8 100644
--- a/bin/varnishtop/Makefile.am
+++ b/bin/varnishtop/Makefile.am
@@ -2,7 +2,8 @@
 
 AM_CPPFLAGS = \
 	-I$(top_srcdir)/include \
-	-I$(top_builddir)/include
+	-I$(top_builddir)/include \
+	@CURSES_CFLAGS@
 
 bin_PROGRAMS = varnishtop
 
diff --git a/configure.ac b/configure.ac
index 3f7d43744..2417549ac 100644
--- a/configure.ac
+++ b/configure.ac
@@ -218,9 +218,13 @@ CURSES_LIBS="$CURSES_LIB"
 		])
 	])
 ])
+AC_SUBST([CURSES_CFLAGS])
 AC_SUBST([CURSES_LIBS])
 
+save_CFLAGS="${CFLAGS}"
+CFLAGS="${CFLAGS} ${CURSES_CFLAGS}"
 AC_CHECK_HEADERS([ncursesw/curses.h ncursesw.h ncurses/curses.h ncurses.h curses.h])
+CFLAGS="${save_CFLAGS}"
 
 # Checks for header files.
 AC_HEADER_STDC