Fix _Alignas

* don't accept _Alignas as type qualifier (after pointer '*'). * accept type-names within _Alignas * add testcases

Michael Matz committed 7 years ago

Commit 38a6aba1 parent fa0ef915 files · +52 −28Browse files

Unified · Split

5 files

tccgen.c +17 −28
tests/tests2/102_alignas.c +28 −0
tests/tests2/102_alignas.expect +1 −0
tests/tests2/60_errors_and_warnings.c +3 −0
tests/tests2/60_errors_and_warnings.expect +3 −0

             goto basic_type;
         case TOK_ALIGNAS:
             { int n;
-            next();
+              AttributeDef ad1;
-            /* TODO: _Alignas(type) -> _Alignas(_Alignof(type)) */
+              next();
-            if (tok == '(') {
+              skip('(');
-                next();
+              memset(&ad1, 0, sizeof(AttributeDef));
-                n = expr_const();
+              if (parse_btype(&type1, &ad1)) {
-                if (n <= 0 || (n & (n - 1)) != 0)
+                  type_decl(&type1, &ad1, &n, TYPE_ABSTRACT);
+                  if (ad1.a.aligned)
+                    n = 1 << (ad1.a.aligned - 1);
+                  else
+                    type_size(&type1, &n);
+              } else {
+                  n = expr_const();
+                  if (n <= 0 || (n & (n - 1)) != 0)
                     tcc_error("alignment must be a positive power of two");
-                skip(')');
+              }
-            } else {
+              skip(')');
-                 expect("(");
+              ad->a.aligned = exact_log2p1(n);
             }
-            ad->a.aligned = exact_log2p1(n);
+            continue;
-          }
-          continue;
         case TOK_LONG:
             if ((t & VT_BTYPE) == VT_DOUBLE) {
                 t = (t & ~(VT_BTYPE|VT_LONG)) | VT_LDOUBLE;
         case TOK_RESTRICT2:
         case TOK_RESTRICT3:
             goto redo;
-        case TOK_ALIGNAS:
-            { int n;
-            next();
-            /* TODO: _Alignas(type) -> _Alignas(_Alignof(type)) */
-            if (tok == '(') {
-                next();
-                n = expr_const();
-                if (n <= 0 || (n & (n - 1)) != 0)
-                    tcc_error("alignment must be a positive power of two");
-                skip(')');
-            } else {
-                expect("(");
-            }
-            ad->a.aligned = exact_log2p1(n);
-          }
-          break;
 	/* XXX: clarify attribute handling */
 	case TOK_ATTRIBUTE1:
 	case TOK_ATTRIBUTE2:

tests/tests2/102_alignas.c+28−0

@@ -0,0 +1,28 @@
	1	_Alignas(16) int i1;
	2	int _Alignas(16) i2;
	3	void _Alignas(16) *p2;
	4	_Alignas(16) i3;
	5	int _Alignas(double) i4;
	6	int _Alignas(int) i5;
	7	#if 0
	8	/* The following are currently wrongly accepted by TCC but really shouldn't. */
	9	int _Alignas(int _Alignas(16)) i6; //wrong, 'int _Alignas(16)' is no type-name
	10	typedef int _Alignas(16) int16aligned_t; //wrong, _Alignas invalid on typedef
	11	int16aligned_t i7;
	12	#endif
	13	/* i8 should get an alignment of 16, because unlike _Alignas the
	14	corresponding attribute _does_ apply to type-name, though not in
	15	some clang versions. */
	16	int _Alignas(int __attribute__((aligned(16)))) i8;
	17	extern int printf(const char*, ...);
	18	#ifdef _MSC_VER
	19	#define alignof(x) (int)__alignof(x)
	20	#else
	21	#define alignof(x) (int)__alignof__(x)
	22	#endif
	23	int main()
	24	{
	25	printf("%d %d %d %d\n",
	26	alignof(i1), alignof(i4), alignof(i5), alignof(i8));
	27	return 0;
	28	}

tests/tests2/102_alignas.expect+1−0

@@ -0,0 +1 @@
		1	16 8 4

tests/tests2/60_errors_and_warnings.c+3−0

@@ -172,4 +172,7 @@ int X=1; · 171 unmodified lines
172	int main(void) {	172	int main(void) {
173	int t[][][X];	173	int t[][][X];
174	}	174	}
		175	#elif defined test_invalid_alignas
		176	/* _Alignas is no type qualifier */
		177	void * _Alignas(16) p1;
175	#endif	178	#endif

tests/tests2/60_errors_and_warnings.expect+3−0

@@ -80,3 +80,6 @@ · 79 unmodified lines
80		80
81	[test_vla_1]	81	[test_vla_1]
82	60_errors_and_warnings.c:173: error: need explicit inner array size in VLAs	82	60_errors_and_warnings.c:173: error: need explicit inner array size in VLAs
		83
		84	[test_invalid_alignas]
		85	60_errors_and_warnings.c:177: error: identifier expected

Fix _Alignas

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