Check if C++ compiler is present.


git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@3750 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/common/jpeg/configure.ac b/common/jpeg/configure.ac
index 8c23a50..0245458 100644
--- a/common/jpeg/configure.ac
+++ b/common/jpeg/configure.ac
@@ -14,6 +14,7 @@
 # Checks for programs.
 AC_PROG_CPP
 AC_PROG_CC
+AC_PROG_CXX
 AC_PROG_INSTALL
 AC_PROG_LIBTOOL
 AC_PROG_LN_S