--- a/python/c3/typecheck.py	Fri Mar 22 16:15:31 2013 +0100
+++ b/python/c3/typecheck.py	Fri Mar 22 17:40:13 2013 +0100
@@ -28,12 +28,22 @@
             self.diag.error('Cannot assign {0} to {1}'.format(sym.rval.typ, sym.lval.typ), sym.loc)
       elif type(sym) is ReturnStatement:
          pass
-      elif type(sym) is ProcedureCall:
-         # Check arguments:
+      elif type(sym) is FunctionCall:
          if sym.proc:
-            pass
-         # determine return type:
-         sym.typ = sym.proc.typ.returntype
+            # Check arguments:
+            ngiv = len(sym.args)
+            ptypes = sym.proc.typ.parametertypes
+            nreq = len(ptypes)
+            if ngiv != nreq:
+               self.diag.error('Function {2}: {0} arguments required, {1} given'.format(nreq, ngiv, sym.proc.name), sym.loc)
+            else:
+               for a, at in zip(sym.args, ptypes):
+                  if not equalTypes(a.typ, at):
+                     self.diag.error('Got {0}, expected {1}'.format(a.typ, at), a.loc)
+            # determine return type:
+            sym.typ = sym.proc.typ.returntype
+         else:
+            sym.typ = intType
       elif type(sym) is VariableUse:
          if sym.target:
             sym.typ = sym.target.typ