c variadic calls

compiler/parser/parser.odin

@@ -889,11 +889,27 @@ parse_statement :: proc(parser: ^Parser) -> ast.Stmt_Id {
 	return id
 }
 
-parse_params :: proc(parser: ^Parser) -> []ast.Param {
+parse_params :: proc(parser: ^Parser) -> ([]ast.Param, bool) {
 	params: [dynamic]ast.Param
 	params.allocator = parser.module.allocator
+	variadic := false
 	skip_newlines(parser)
 	for current(parser).kind != .Right_Paren && current(parser).kind != .Eof {
+		if current(parser).kind == .Ellipsis {
+			marker := advance(parser)
+			if variadic {
+				source.add(parser.diagnostics, marker.span, "duplicate variadic marker")
+			}
+			variadic = true
+			skip_newlines(parser)
+			if _, ok := allow(parser, .Comma); ok {
+				skip_newlines(parser)
+			}
+			if current(parser).kind != .Right_Paren {
+				source.add(parser.diagnostics, current(parser).span, "variadic marker must be the final parameter")
+			}
+			continue
+		}
 		names: [dynamic]token.Token
 		names.allocator = parser.module.allocator
 		for {
@@ -923,7 +939,7 @@ parse_params :: proc(parser: ^Parser) -> []ast.Param {
 		}
 		break
 	}
-	return params[:]
+	return params[:], variadic
 }
 
 parse_function :: proc(parser: ^Parser, name: token.Token, c_abi: bool) {
@@ -931,7 +947,7 @@ parse_function :: proc(parser: ^Parser, name: token.Token, c_abi: bool) {
 	if _, ok := allow(parser, .Left_Paren); !ok {
 		source.add(parser.diagnostics, current(parser).span, "expected '(' after 'func'")
 	}
-	params := parse_params(parser)
+	params, variadic := parse_params(parser)
 	if _, ok := allow(parser, .Right_Paren); !ok {
 		source.add(parser.diagnostics, current(parser).span, "expected ')' after parameters")
 	}
@@ -954,6 +970,7 @@ parse_function :: proc(parser: ^Parser, name: token.Token, c_abi: bool) {
 			file=parser.file,
 			c_abi=c_abi,
 			has_body=false,
+			variadic=variadic,
 			params=params,
 			result=result,
 			diagnostic=source.INVALID_DIAGNOSTIC,
@@ -991,6 +1008,7 @@ parse_function :: proc(parser: ^Parser, name: token.Token, c_abi: bool) {
 		file=parser.file,
 		c_abi=c_abi,
 		has_body=true,
+		variadic=variadic,
 		params=params,
 		result=result,
 		body=body[:],