Merged mcb30-realmode-redesign back to HEAD

src/include/compiler.h

@@ -0,0 +1,41 @@
+#ifndef COMPILER_H
+#define COMPILER_H
+
+/* We export the symbol obj_OBJECT (OBJECT is defined on command-line)
+ * as a global symbol, so that the linker can drag in selected object
+ * files from the library using -u obj_OBJECT.
+ *
+ * Not quite sure why cpp requires two levels of macro call in order
+ * to actually expand OBJECT...
+ */
+#undef _H1
+#define _H1( x, y ) x ## y
+#undef _H2
+#define _H2( x, y ) _H1 ( x, y )
+#define OBJECT_SYMBOL _H2 ( obj_, OBJECT )
+#undef _STR
+#define _STR(s) #s
+#undef _XSTR
+#define _XSTR(s) _STR(s)
+#define OBJECT_SYMBOL_STR _XSTR ( OBJECT_SYMBOL )
+
+#ifdef ASSEMBLY
+
+	.globl	OBJECT_SYMBOL
+	.equ	OBJECT_SYMBOL, 0
+
+#else /* ASSEMBLY */
+
+__asm__ ( ".globl\t" OBJECT_SYMBOL_STR );
+__asm__ ( ".equ\t" OBJECT_SYMBOL_STR ", 0" );
+
+#define REQUIRE_OBJECT(object) \
+	__asm__ ( ".equ\tneed_" #object ", obj_" #object );
+
+#define PACKED __attribute__((packed))
+#define __unused __attribute__((unused))
+#define __used __attribute__((used))
+
+#endif /* ASSEMBLY */
+
+#endif /* COMPILER_H */