manual c function interop

compiler/parser/parser.odin

@@ -385,10 +385,29 @@ parse_function :: proc(parser: ^Parser, name: token.Token, c_abi: bool) {
 	}
 	skip_newlines(parser)
 	result := parse_type(parser)
-	skip_newlines(parser)
-	if _, ok := allow(parser, .Left_Brace); !ok {
-		source.add(parser.diagnostics, current(parser).span, "expected '{' before function body")
+	end := previous(parser)
+	ended_by_newline := current(parser).kind == .Newline
+	if current(parser).kind == .Newline {
+		skip_newlines(parser)
 	}
+	if current(parser).kind != .Left_Brace {
+		if !ended_by_newline && current(parser).kind != .Eof {
+			_ = finish_statement(parser)
+		}
+		append(&parser.module.functions, ast.Function{
+			span=span_from(name.span, end.span),
+			name=name.symbol,
+			pkg=parser.pkg,
+			file=parser.file,
+			c_abi=c_abi,
+			has_body=false,
+			params=params,
+			result=result,
+			diagnostic=-1,
+		})
+		return
+	}
+	advance(parser)
 
 	body: [dynamic]int
 	body.allocator = parser.module.allocator
@@ -406,7 +425,7 @@ parse_function :: proc(parser: ^Parser, name: token.Token, c_abi: bool) {
 			append(&body, statement_id)
 		}
 	}
-	end := current(parser)
+	end = current(parser)
 	if _, ok := allow(parser, .Right_Brace); !ok {
 		source.add(parser.diagnostics, current(parser).span, "expected '}' after function body")
 		end = func_token
@@ -417,6 +436,7 @@ parse_function :: proc(parser: ^Parser, name: token.Token, c_abi: bool) {
 		pkg=parser.pkg,
 		file=parser.file,
 		c_abi=c_abi,
+		has_body=true,
 		params=params,
 		result=result,
 		body=body[:],