Ignore some more attributes

Detected when using -Wunsupported

Author: hermantb

tccgen.c

@@ -4013,11 +4013,27 @@ static void parse_attribute(AttributeDef *ad)
         case TOK_NODEBUG2:
             ad->a.nodebug = 1;
             break;
+        case TOK_USED1:
+        case TOK_USED2:
         case TOK_UNUSED1:
         case TOK_UNUSED2:
             /* currently, no need to handle it because tcc does not
-               track unused objects */
+               track used/unused objects */
             break;
+        case TOK_CONST1:
+        case TOK_CONST2:
+        case TOK_CONST3:
+        case TOK_PURE1:
+        case TOK_PURE2:
+	    /* ignored */
+            break;
+        case TOK_NOINLINE:
+	    /* ignored */
+	    break;
+        case TOK_FORMAT1:
+        case TOK_FORMAT2:
+	    /* ignored */
+            goto skip_param;
         case TOK_NORETURN1:
         case TOK_NORETURN2:
             ad->f.func_noreturn = 1;
@@ -4091,6 +4107,7 @@ static void parse_attribute(AttributeDef *ad)
         default:
             tcc_warning_c(warn_unsupported)("'%s' attribute ignored", get_tok_str(t, NULL));
             /* skip parameters */
+skip_param:
             if (tok == '(') {
                 int parenthesis = 0;
                 do {

tcctok.h

@@ -23,6 +23,8 @@
      DEF(TOK_CONST1, "const")
      DEF(TOK_CONST2, "__const") /* gcc keyword */
      DEF(TOK_CONST3, "__const__") /* gcc keyword */
+     DEF(TOK_PURE1, "pure")
+     DEF(TOK_PURE2, "__pure__")
      DEF(TOK_VOLATILE1, "volatile")
      DEF(TOK_VOLATILE2, "__volatile") /* gcc keyword */
      DEF(TOK_VOLATILE3, "__volatile__") /* gcc keyword */
@@ -114,8 +116,12 @@
      DEF(TOK_WEAK2, "__weak__")
      DEF(TOK_ALIAS1, "alias")
      DEF(TOK_ALIAS2, "__alias__")
+     DEF(TOK_USED1, "used")
+     DEF(TOK_USED2, "__used__")
      DEF(TOK_UNUSED1, "unused")
      DEF(TOK_UNUSED2, "__unused__")
+     DEF(TOK_FORMAT1, "format")
+     DEF(TOK_FORMAT2, "__format__")
      DEF(TOK_NODEBUG1, "nodebug")
      DEF(TOK_NODEBUG2, "__nodebug__")
      DEF(TOK_CDECL1, "cdecl")
@@ -140,6 +146,7 @@
      DEF(TOK_DESTRUCTOR2, "__destructor__")
      DEF(TOK_ALWAYS_INLINE1, "always_inline")
      DEF(TOK_ALWAYS_INLINE2, "__always_inline__")
+     DEF(TOK_NOINLINE, "__noinline__")
 
      DEF(TOK_MODE, "__mode__")
      DEF(TOK_MODE_QI, "__QI__")