README: Add C89 compiler to requirements.

diff --git a/README b/README
index 3c802817b8dd64af7c1cd95bc9fae00e457b6e45..83b2442feaef4dbc2803127f947f38e6cbae3e65 100644 (file)
--- a/README
+++ b/README
@@ -11,6 +11,7 @@ tlsproxy is licensed under GPL 3 (or later).
 REQUIREMENTS
 ------------
 
+- C89 compiler
 - GnuTLS library including development headers
 - certtool (from GnuTLS) to create TLS certificates