No more ; needed

Author: OpenCode[AI]

AGENTS.md

@@ -38,3 +38,17 @@
 - Some tests need special flags (see `FLAGS =` assignments in `tests/tests2/Makefile`).
 - Bound-check tests (`-b` flag) are skipped when `CONFIG_bcheck=no`.
 - `.expect` files are generated with gcc by default; some use TCC (flagged with `GEN-TCC`).
+
+## Language Extension: Optional Semicolons
+
+Semicolons are optional after most statements and declarations:
+- `return`, `break`, `continue`, `goto`, expression statements
+- `do-while` trailing semicolon
+- Variable declarations
+
+Semicolons are still **required** for:
+- `for()` loop init/condition/increment sections (e.g., `for(i=0; i<n; i++)`)
+- Old-style function parameter declarations
+- Struct/enum member declarations
+
+The `skip(';')` function in `tccpp.c:100` errors if token doesn't match. Use `if (tok == ';') next();` instead to make semicolons optional.

tccgen.c

@@ -7205,7 +7205,7 @@ static void block(int flags)
                 label_push(&local_label_stack, tok, LABEL_DECLARED);
                 next();
             } while (tok == ',');
-            skip(';');
+            if (tok == ';') next();
         }
 
         while (tok != '}') {
@@ -7241,7 +7241,7 @@ static void block(int flags)
         leave_scope(root_scope);
         if (b)
             gfunc_return(&func_vt);
-        skip(';');
+        if (tok == ';') next();
         /* jump unless last stmt in top-level block */
         if (tok != '}' || local_scope != 1)
             rsym = gjmp(rsym);
@@ -7258,15 +7258,15 @@ static void block(int flags)
         else
             leave_scope(loop_scope);
         *cur_scope->bsym = gjmp(*cur_scope->bsym);
-        skip(';');
+        if (tok == ';') next();
 
     } else if (t == TOK_CONTINUE) {
         /* compute jump */
         if (!cur_scope->csym)
             tcc_error("cannot continue");
         leave_scope(loop_scope);
         *cur_scope->csym = gjmp(*cur_scope->csym);
-        skip(';');
+        if (tok == ';') next();
 
     } else if (t == TOK_FOR) {
         new_scope(&o);
@@ -7314,7 +7314,7 @@ static void block(int flags)
 	gexpr();
         c = gvtst(0, 0);
         skip(')');
-        skip(';');
+        if (tok == ';') next();
 	gsym_addr(c, d);
         gsym(a);
         prev_scope_s(&o);
@@ -7426,7 +7426,7 @@ static void block(int flags)
         } else {
             expect("label identifier");
         }
-        skip(';');
+        if (tok == ';') next();
 
     } else if (t == TOK_ASM1 || t == TOK_ASM2 || t == TOK_ASM3) {
         asm_instr();
@@ -7481,7 +7481,7 @@ static void block(int flags)
                     gexpr();
                     vpop();
                 }
-                skip(';');
+                if (tok == ';') next();
             }
         }
     }
@@ -8637,7 +8637,7 @@ static void do_Static_assert(void)
     skip(')');
     if (c == 0)
         tcc_error("%s", msg);
-    skip(';');
+    if (tok == ';') next();
 }
 
 #ifdef TCC_TARGET_PE
@@ -8718,6 +8718,10 @@ static int decl(int l)
                 return 1;
             next();
             continue;
+        } else if (l != VT_JMP && l != VT_CMP) {
+            /* no semicolon - let caller handle it */
+        } else {
+            expect(";");
         }
 
         while (1) { /* iterate thru each declaration */
@@ -8904,7 +8908,7 @@ static int decl(int l)
                 if (tok != ',') {
                     if (l == VT_JMP)
                         return has_init ? v : 1;
-                    skip(';');
+                    if (tok == ';') next();
                     break;
                 }
                 next();

tests/tests2/60_errors_and_warnings.expect

@@ -179,7 +179,7 @@ bar  : 3 ; 3
 60_errors_and_warnings.c:372: error: statement expression outside of function
 
 [test_invalid_tokckill]
-60_errors_and_warnings.c:375: error: ';' expected (got '3')
+60_errors_and_warnings.c:375: warning: function might return no value: 'f'
 
 [test_duplicate_member]
 60_errors_and_warnings.c:381: error: duplicate member 'a'