Commit Diff


commit - 4e32d3a6c187dd9646ba4aa80a69082adf3b3c46
commit + 268c151ac9fb8f80039e9e1a6fedc6f73c1c79ff
blob - 5e7afa00b7831e398396e466f1b9823620507079
blob + de52ae6fa787bc5c66f15fc3ecf26f8f4ae85a97
--- configure.ac
+++ configure.ac
@@ -8,6 +8,12 @@ AC_PROG_CC
 AC_USE_SYSTEM_EXTENSIONS
 AC_PROG_YACC
 
+# AC_PROC_YACC sets the environment variable $YACC for a suitable program to
+# use, but doesn't check to see if it exists.  Test for this -- if it's not
+# present, error out.
+AC_CHECK_PROG(found_yacc, $YACC, yes, no)
+AS_IF([test "x$found_yacc" = "xno"], [AC_MSG_ERROR("yacc/bison not found")])
+
 PKG_PROG_PKG_CONFIG
 
 AC_ARG_VAR(HOSTCC, [The C compiler on the host.])