[arabic/win1256] Remove GCC'ism

The table can now compile independently too.  If we cannot make it work
on MSVC, we can always generate the data and distribute it.

The code now compiles cleanly with:

gcc -c -xc -std=c99 -Werror -pedantic hb-ot-shape-complex-arabic-win1256.hh
g++ -c -xc -std=c++1x -Werror -pedantic hb-ot-shape-complex-arabic-win1256.hh

See:
https://github.com/behdad/harfbuzz/commit/a97f537cec209649302899975d76ca2b2661da7a#commitcomment-7218736

src/hb-ot-shape-complex-arabic-fallback.hh

@@ -223,7 +223,7 @@ static const arabic_fallback_plan_t arabic_fallback_plan_nil = {};
 #endif
 
 struct ManifestLookup {
-  OT::USHORT fallbackType;
+  OT::Tag tag;
   OT::OffsetTo<OT::SubstLookup> lookupOffset;
 };
 typedef OT::ArrayOf<ManifestLookup> Manifest;
@@ -252,7 +252,7 @@ arabic_fallback_plan_init_win1256 (arabic_fallback_plan_t *fallback_plan,
   unsigned int count = manifest.len;
   for (unsigned int i = 0; i < count; i++)
   {
-    fallback_plan->mask_array[j] = plan->map.get_1_mask (manifest[i].fallbackType);
+    fallback_plan->mask_array[j] = plan->map.get_1_mask (manifest[i].tag);
     if (fallback_plan->mask_array[j])
     {
       fallback_plan->lookup_array[j] = const_cast<OT::SubstLookup*> (&(&manifest+manifest[i].lookupOffset));

src/hb-ot-shape-complex-arabic-win1256.hh

@@ -39,78 +39,92 @@
 /* First we measure, then we cut. */
 #ifndef OT_MEASURE
 #define OT_MEASURE
-#define OT_TABLE_START			static const struct TABLE_NAME { char start[0
-#define OT_TABLE_END			]; }
-#define OT_LABEL(Name)			]; char Name[0
+#define OT_TABLE_START			static const struct TABLE_NAME {
+#define OT_TABLE_END			}
+#define OT_LABEL_START(Name)		unsigned char Name[
+#define OT_LABEL_END			];
+#define OT_BYTE(u8)			+1/*byte*/
 #define OT_USHORT(u16)			+2/*bytes*/
-#define OT_DISTANCE(From,To,ItemSize)	0/*don't care */
 #else
 #undef  OT_MEASURE
-#define OT_TABLE_START			TABLE_NAME = { {
-#define OT_TABLE_END			} };
-#define OT_LABEL(Name)			}, {
-#define OT_USHORT(u16)			((u16)>>8), ((u16)&0xFF),
-#define OT_DISTANCE(From,To,ItemSize)	((offsetof (struct TABLE_NAME, To) - \
-					  offsetof (struct TABLE_NAME, From)) / (ItemSize) \
-					 /* ASSERT_STATIC_EXPR it's divisible. */)
+#define OT_TABLE_START			TABLE_NAME = {
+#define OT_TABLE_END			};
+#define OT_LABEL_START(Name)		{
+#define OT_LABEL_END			},
+#define OT_BYTE(u8)			(u8),
+#define OT_USHORT(u16)			(unsigned char)((u16)>>8), (unsigned char)((u16)&0xFFu),
+#define OT_COUNT(Name, ItemSize)	((unsigned int) sizeof(((struct TABLE_NAME*)0)->Name) \
+					 / (unsigned int)(ItemSize) \
+					 /* OT_ASSERT it's divisible (and positive). */)
+#define OT_DISTANCE(From,To)		((unsigned int) \
+					 ((char*)(&((struct TABLE_NAME*)0)->To) - \
+					  (char*)(&((struct TABLE_NAME*)0)->From)) \
+					 /* OT_ASSERT it's positive. */)
 #endif
 
 
+#define OT_LABEL(Name) \
+	OT_LABEL_END \
+	OT_LABEL_START(Name)
+
 /* Whenever we receive an argument that is a list, it will expand to
  * contain commas.  That cannot be passed to another macro because the
  * commas will throw off the preprocessor.  The solution is to wrap
  * the passed-in argument in OT_LIST() before passing to the next macro.
  * Unfortunately this trick requires vararg macros. */
-#define OT_LIST(Args...) Args
+#define OT_LIST(...) __VA_ARGS__
 
 
 /*
  * Basic Types
  */
 
-#define OT_OFFSET(From, To) \
-	OT_USHORT(OT_DISTANCE(From, To, 1)) // Offset from From to To in bytes
+#define OT_TAG(a,b,c,d) \
+	OT_BYTE(a) OT_BYTE(b) OT_BYTE(c) OT_BYTE(d)
 
-#define OT_COUNT(Start, End, ItemSize) \
-	OT_USHORT(OT_DISTANCE(Start, End, ItemSize))
-#define OT_UCOUNT(Start,End) \
-	OT_COUNT(Start, End, 2) // USHORT count
+#define OT_OFFSET(From, To) /* Offset from From to To in bytes */ \
+	OT_USHORT(OT_DISTANCE(From, To))
 
-#define OT_GLYPHID	OT_USHORT // GlyphID
+#define OT_GLYPHID /* GlyphID */ \
+	OT_USHORT
 
 #define OT_UARRAY(Name, Items) \
-	OT_LABEL(Name) \
-	OT_UCOUNT(Name##Data, Name##DataEnd) \
+	OT_LABEL_START(Name) \
+	OT_USHORT(OT_COUNT(Name##Data, 2)) \
 	OT_LABEL(Name##Data) \
 	Items \
-	OT_LABEL(Name##DataEnd)
+	OT_LABEL_END
 
 #define OT_UHEADLESSARRAY(Name, Items) \
-	OT_LABEL(Name) \
-	OT_USHORT(OT_DISTANCE(Name##Data, Name##DataEnd, 2) + 1) \
+	OT_LABEL_START(Name) \
+	OT_USHORT(OT_COUNT(Name##Data, 2) + 1) \
 	OT_LABEL(Name##Data) \
 	Items \
-	OT_LABEL(Name##DataEnd)
+	OT_LABEL_END
 
 
 /*
  * Common Types
  */
 
+#define OT_LOOKUP_FLAG_IGNORE_MARKS	0x08u
+
 #define OT_LOOKUP(Name, LookupType, LookupFlag, SubLookupOffsets) \
-	OT_LABEL(Name) \
+	OT_LABEL_START(Name) \
 	OT_USHORT(LookupType) \
 	OT_USHORT(LookupFlag) \
+	OT_LABEL_END \
 	OT_UARRAY(Name##SubLookupOffsetsArray, OT_LIST(SubLookupOffsets))
 
 #define OT_SUBLOOKUP(Name, SubFormat, Items) \
-	OT_LABEL(Name) \
+	OT_LABEL_START(Name) \
 	OT_USHORT(SubFormat) \
 	Items
 
 #define OT_COVERAGE1(Name, Items) \
-	OT_LABEL(Name) \
+	OT_LABEL_START(Name) \
 	OT_USHORT(1) \
+	OT_LABEL_END \
 	OT_UARRAY(Name##Glyphs, OT_LIST(Items))
 
 
@@ -118,9 +132,14 @@
  * GSUB
  */
 
+#define OT_LOOKUP_TYPE_SUBST_SINGLE	1u
+#define OT_LOOKUP_TYPE_SUBST_MULTIPLE	2u
+#define OT_LOOKUP_TYPE_SUBST_LIGATURE	4u
+
 #define OT_SUBLOOKUP_SINGLE_SUBST_FORMAT2(Name, FromGlyphs, ToGlyphs) \
 	OT_SUBLOOKUP(Name, 2, \
 		OT_OFFSET(Name, Name##Coverage) \
+		OT_LABEL_END \
 		OT_UARRAY(Name##Substitute, OT_LIST(ToGlyphs)) \
 	) \
 	OT_COVERAGE1(Name##Coverage, OT_LIST(FromGlyphs)) \
@@ -129,30 +148,31 @@
 #define OT_SUBLOOKUP_MULTIPLE_SUBST_FORMAT1(Name, FromGlyphs, SequenceOffsets) \
 	OT_SUBLOOKUP(Name, 1, \
 		OT_OFFSET(Name, Name##Coverage) \
+		OT_LABEL_END \
 		OT_UARRAY(Name##SequenceOffsetsArray, OT_LIST(SequenceOffsets)) \
 	) \
 	OT_COVERAGE1(Name##Coverage, OT_LIST(FromGlyphs)) \
 	/* ASSERT_STATIC_EXPR len(FromGlyphs) == len(SequenceOffsets) */
 
 #define OT_SEQUENCE(Name, SubstituteGlyphs) \
-	OT_LABEL(Name) \
-	OT_UARRAY(Name##SubstituteGlyphsArray, OT_LIST(SubstituteGlyphs))
+	OT_UARRAY(Name, OT_LIST(SubstituteGlyphs))
 
 #define OT_SUBLOOKUP_LIGATURE_SUBST_FORMAT1(Name, FirstGlyphs, LigatureSetOffsets) \
 	OT_SUBLOOKUP(Name, 1, \
 		OT_OFFSET(Name, Name##Coverage) \
+		OT_LABEL_END \
 		OT_UARRAY(Name##LigatureSetOffsetsArray, OT_LIST(LigatureSetOffsets)) \
 	) \
 	OT_COVERAGE1(Name##Coverage, OT_LIST(FirstGlyphs)) \
 	/* ASSERT_STATIC_EXPR len(FirstGlyphs) == len(LigatureSetOffsets) */
 
 #define OT_LIGATURE_SET(Name, LigatureSetOffsets) \
-	OT_LABEL(Name) \
-	OT_UARRAY(Name##LigatureSetOffsetsArray, OT_LIST(LigatureSetOffsets))
+	OT_UARRAY(Name, OT_LIST(LigatureSetOffsets))
 
 #define OT_LIGATURE(Name, Components, LigGlyph) \
-	OT_LABEL(Name) \
+	OT_LABEL_START(Name) \
 	LigGlyph \
+	OT_LABEL_END \
 	OT_UHEADLESSARRAY(Name##ComponentsArray, OT_LIST(Components))
 
 
@@ -167,14 +187,14 @@
 
 /* Table manifest. */
 #define MANIFEST(Items) \
-	OT_LABEL(manifest) \
-	OT_COUNT(manifestData, manifestDataEnd, 4) \
+	OT_LABEL_START(manifest) \
+	OT_USHORT(OT_COUNT(manifestData, 6)) \
 	OT_LABEL(manifestData) \
 	Items \
-	OT_LABEL(manifestDataEnd)
+	OT_LABEL_END
 
-#define MANIFEST_LOOKUP(FallbackType, Name) \
-	OT_USHORT(FallbackType) \
+#define MANIFEST_LOOKUP(Tag, Name) \
+	Tag \
 	OT_OFFSET(manifest, Name)
 
 /* Shorthand. */
@@ -202,34 +222,34 @@ OT_TABLE_START
  * Manifest
  */
 MANIFEST(
-	MANIFEST_LOOKUP(FALLBACK_INIT, initLookup)
-	MANIFEST_LOOKUP(FALLBACK_MEDI, mediLookup)
-	MANIFEST_LOOKUP(FALLBACK_FINA, finaLookup)
-	MANIFEST_LOOKUP(FALLBACK_RLIG, rligLookup)
-	MANIFEST_LOOKUP(FALLBACK_RLIG, rligMarksLookup)
+	MANIFEST_LOOKUP(OT_TAG('i','n','i','t'), initLookup)
+	MANIFEST_LOOKUP(OT_TAG('m','e','d','i'), mediLookup)
+	MANIFEST_LOOKUP(OT_TAG('f','i','n','a'), finaLookup)
+	MANIFEST_LOOKUP(OT_TAG('r','l','i','g'), rligLookup)
+	MANIFEST_LOOKUP(OT_TAG('r','l','i','g'), rligMarksLookup)
 )
 
 /*
  * Lookups
  */
-OT_LOOKUP(initLookup, OT::SubstLookupSubTable::Single, OT::LookupFlag::IgnoreMarks,
+OT_LOOKUP(initLookup, OT_LOOKUP_TYPE_SUBST_SINGLE, OT_LOOKUP_FLAG_IGNORE_MARKS,
 	OT_OFFSET(initLookup, initmediSubLookup)
 	OT_OFFSET(initLookup, initSubLookup)
 )
-OT_LOOKUP(mediLookup, OT::SubstLookupSubTable::Single, OT::LookupFlag::IgnoreMarks,
+OT_LOOKUP(mediLookup, OT_LOOKUP_TYPE_SUBST_SINGLE, OT_LOOKUP_FLAG_IGNORE_MARKS,
 	OT_OFFSET(mediLookup, initmediSubLookup)
 	OT_OFFSET(mediLookup, mediSubLookup)
 )
-OT_LOOKUP(finaLookup, OT::SubstLookupSubTable::Single, OT::LookupFlag::IgnoreMarks,
+OT_LOOKUP(finaLookup, OT_LOOKUP_TYPE_SUBST_SINGLE, OT_LOOKUP_FLAG_IGNORE_MARKS,
 	OT_OFFSET(finaLookup, finaSubLookup)
 )
-OT_LOOKUP(mediLamLookup, OT::SubstLookupSubTable::Multiple, OT::LookupFlag::IgnoreMarks,
+OT_LOOKUP(mediLamLookup, OT_LOOKUP_TYPE_SUBST_MULTIPLE, OT_LOOKUP_FLAG_IGNORE_MARKS,
 	OT_OFFSET(mediLamLookup, mediLamSubLookup)
 )
-OT_LOOKUP(rligLookup, OT::SubstLookupSubTable::Ligature, OT::LookupFlag::IgnoreMarks,
+OT_LOOKUP(rligLookup, OT_LOOKUP_TYPE_SUBST_LIGATURE, OT_LOOKUP_FLAG_IGNORE_MARKS,
 	OT_OFFSET(rligLookup, lamAlefLigaturesSubLookup)
 )
-OT_LOOKUP(rligMarksLookup, OT::SubstLookupSubTable::Ligature, 0,
+OT_LOOKUP(rligMarksLookup, OT_LOOKUP_TYPE_SUBST_LIGATURE, 0,
 	OT_OFFSET(rligMarksLookup, shaddaLigaturesSubLookup)
 )
 
@@ -313,9 +333,12 @@ OT_TABLE_END
  */
 #undef OT_TABLE_START
 #undef OT_TABLE_END
-#undef OT_LABEL
+#undef OT_LABEL_START
+#undef OT_LABEL_END
+#undef OT_BYTE
 #undef OT_USHORT
 #undef OT_DISTANCE
+#undef OT_COUNT
 
 /*
  * Include a second time to get the table data...