--- configure.ac.orig	2021-04-17 06:49:29 UTC
+++ configure.ac
@@ -41,6 +41,7 @@ AC_PROG_CC_C99
 if test x"$ac_cv_prog_cc_c99" = xno; then
     AC_MSG_ERROR([C99 compiler is required.])
 fi
+AC_PROG_CPP
 AC_PROG_INSTALL
 AC_CANONICAL_HOST
 LT_INIT([disable-static])
@@ -204,7 +205,8 @@ AS_VAR_APPEND([SPICE_REQUIRES], [" pixman-1 >= $PIXMAN
 PKG_CHECK_MODULES(SSL, openssl >= 1.0.0)
 AC_SUBST(SSL_CFLAGS)
 AC_SUBST(SSL_LIBS)
-AS_VAR_APPEND([SPICE_REQUIRES], [" openssl"])
+dnl OpenSSL in the base system is not managed by pkgconfig
+dnl AS_VAR_APPEND([SPICE_REQUIRES], [" openssl"])
 
 save_CFLAGS="$CFLAGS"
 CFLAGS="$CFLAGS $SSL_CFLAGS"
@@ -217,15 +219,16 @@ CFLAGS="$save_CFLAGS"
 
 AC_CHECK_LIB(jpeg, jpeg_destroy_decompress,
     AC_MSG_CHECKING([for jpeglib.h])
-    AC_TRY_CPP(
-[#include <stdio.h>
+    AC_PREPROC_IFELSE(
+[AC_LANG_SOURCE([[
+#include <stdio.h>
 #undef PACKAGE
 #undef VERSION
 #undef HAVE_STDLIB_H
-#include <jpeglib.h>],
-        JPEG_LIBS='-ljpeg'
-        AC_MSG_RESULT($jpeg_ok),
-	AC_MSG_ERROR([jpeglib.h not found])),
+#include <jpeglib.h>]])],
+        [JPEG_LIBS='-ljpeg'
+        AC_MSG_RESULT($jpeg_ok)],
+	[AC_MSG_ERROR([jpeglib.h not found])]),
     AC_MSG_ERROR([libjpeg not found]))
 AC_SUBST(JPEG_LIBS)