- * in GCC later than version 2.7 or so. If you are using some
- * compiler that doesn't understand this, you could could just
- * change it to "typedef void never_returns" and nothing would
- * break, though you might get a few more bytes of compiled code or
- * a few more compiler warnings. -- WHN 2000-10-21 */
-typedef volatile void never_returns;
+ * in GCC later than version 2.5 or so. */
+#if defined(__GNUC__)
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 5)
+#define never_returns __attribute__ ((noreturn))
+#else
+#define never_returns
+#endif
+#else
+#define never_returns
+#endif
+
+extern void *successful_malloc (size_t size);
+extern char *copied_string (char *string);
+
+#if defined(LISP_FEATURE_SB_THREAD) && !defined(LISP_FEATURE_SB_SAFEPOINT)
+# define THREADS_USING_GCSIGNAL 1
+#endif
+
+/* Now that SPARC has precise GENCGC, several places that used to be
+ * #ifdef PCC need adjustment. Clearly, "PPC or SPARC" is as unhelpful
+ * a test as its reverse, "x86 or x86-64". However, the feature
+ * commonly used to differentiate between those two worlds is
+ * C_STACK_IS_CONTROL_STACK, and clearly (or at least in my humble
+ * opinion), at some point we'd like to have precise GC on x86 while
+ * still sharing the C stack, so stack usage ought not imply GC
+ * conservativeness. So let's have a helper feature that makes the code
+ * a bit more future-proof, even if it is itself currently defined in
+ * the naive way: */
+#if defined(LISP_FEATURE_GENCGC) && !defined(LISP_FEATURE_C_STACK_IS_CONTROL_STACK)
+# define GENCGC_IS_PRECISE 1
+#endif
+
+void *os_dlsym_default(char *name);