Handle functions with anonymous arguments

Example:

int f(int a, int, int c) {
    return a + c;
}

libacc/acc.cpp

@@ -4891,11 +4891,15 @@ class Compiler : public ErrorSink {
                     int argCount = 0;
                     for (Type* pP = pDecl->pTail; pP; pP = pP->pTail) {
                         Type* pArg = pP->pHead;
-                        addLocalSymbol(pArg);
+                        if (pArg->id) {
+                            addLocalSymbol(pArg);
+                        }
                         /* read param name and compute offset */
                         size_t alignment = pGen->stackAlignmentOf(pArg);
                         a = (a + alignment - 1) & ~ (alignment-1);
-                        VI(pArg->id)->pAddress = (void*) a;
+                        if (pArg->id) {
+                            VI(pArg->id)->pAddress = (void*) a;
+                        }
                         a = a + pGen->stackSizeOf(pArg);
                         argCount++;
                     }

libacc/tests/data/funcargs.c

@@ -0,0 +1,8 @@
+int f(int a,int, int c) {
+    return a + c;
+}
+
+int main() {
+    return f(1,2,3);
+}
+

libacc/tests/test.py

@@ -437,6 +437,11 @@ result: 0
     def testDefines(self):
         self.compileCheck(["-R", "data/defines.c"], """Executing compiled code:
 result: 3
+""","""""")
+
+    def testFuncArgs(self):
+        self.compileCheck(["-R", "data/funcargs.c"], """Executing compiled code:
+result: 4
 ""","""""")
 
 def main():