Allow variadic functions to be called

chibi.h

@@ -212,6 +212,7 @@ struct Function {
   char *name;
   VarList *params;
   bool is_static;
+  bool has_varargs;
 
   Node *node;
   VarList *locals;

parse.c

@@ -609,25 +609,30 @@ static VarList *read_func_param(void) {
   return vl;
 }
 
-static VarList *read_func_params(void) {
+static void read_func_params(Function *fn) {
   if (consume(")"))
-    return NULL;
+    return;
 
   Token *tok = token;
   if (consume("void") && consume(")"))
-    return NULL;
+    return;
   token = tok;
 
-  VarList *head = read_func_param();
-  VarList *cur = head;
+  fn->params = read_func_param();
+  VarList *cur = fn->params;
 
   while (!consume(")")) {
     expect(",");
+
+    if (consume("...")) {
+      fn->has_varargs = true;
+      expect(")");
+      return;
+    }
+
     cur->next = read_func_param();
     cur = cur->next;
   }
-
-  return head;
 }
 
 // function = basetype declarator "(" params? ")" ("{" stmt* "}" | ";")
@@ -651,7 +656,7 @@ static Function *function(void) {
   expect("(");
 
   Scope *sc = enter_scope();
-  fn->params = read_func_params();
+  read_func_params(fn);
 
   if (consume(";")) {
     leave_scope(sc);

self.sh

@@ -36,7 +36,6 @@ EOF
     sed -i 's/\berrno\b/*__errno_location()/g' $TMP/$1
     sed -i 's/\btrue\b/1/g; s/\bfalse\b/0/g;' $TMP/$1
     sed -i 's/\bNULL\b/0/g' $TMP/$1
-    sed -i 's/, \.\.\.//g' $TMP/$1
     sed -i 's/INT_MAX/2147483647/g' $TMP/$1
 
     ./chibicc $TMP/$1 > $TMP/${1%.c}.s

tests

@@ -137,6 +137,9 @@ int counter() {
 _Bool true_fn();
 _Bool false_fn();
 
+int add_all1(int x, ...);
+int add_all3(int z, int b, int c, ...);
+
 int main() {
   assert(8, ({ int a=3; int z=5; a+z; }), "int a=3; int z=5; a+z;");
 
@@ -700,6 +703,12 @@ int main() {
   assert(1, true_fn(), "true_fn()");
   assert(0, false_fn(), "false_fn()");
 
+  assert(6, add_all1(1,2,3,0), "add_all1(1,2,3,0)");
+  assert(5, add_all1(1,2,3,-1,0), "add_all1(1,2,3,-1,0)");
+
+  assert(6, add_all3(1,2,3,0), "add_all3(1,2,3,0)");
+  assert(5, add_all3(1,2,3,-1,0), "add_all3(1,2,3,-1,0)");
+
   printf("OK\n");
   return 0;
 }

tests-extern

@@ -1,7 +1,34 @@
 // -*- c -*-
+#include <stdarg.h>
+
 int ext1;
 int *ext2;
 
 int false_fn() { return 512; }
 int true_fn() { return 513; }
 int static_fn() { return 5; }
+
+int add_all1(int x, ...) {
+  va_list ap;
+  va_start(ap, x);
+
+  for (;;) {
+    int y = va_arg(ap, int);
+    if (y == 0)
+      return x;
+    x += y;
+  }
+}
+
+int add_all3(int x, int y, int z, ...) {
+  va_list ap;
+  va_start(ap, z);
+  x = x + y + z;
+
+  for (;;) {
+    int y = va_arg(ap, int);
+    if (y == 0)
+      return x;
+    x += y;
+  }
+}

tokenize.c

@@ -160,8 +160,8 @@ static char *starts_with_reserved(char *p) {
   }
 
   // Multi-letter punctuator
-  static char *ops[] = {"<<=", ">>=", "==", "!=", "<=", ">=", "->",
-                        "++", "--", "<<", ">>", "+=", "-=", "*=",
+  static char *ops[] = {"<<=", ">>=", "...", "==", "!=", "<=", ">=",
+                        "->", "++", "--", "<<", ">>", "+=", "-=", "*=",
                         "/=", "&&", "||", "&=", "|=", "^="};
 
   for (int i = 0; i < sizeof(ops) / sizeof(*ops); i++)