X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fruntime%2Fbsd-os.h;h=7b094c373e1fc06b41f13ffbf33727685e6fa6e4;hb=4cf50b1896b25f5337e7c258b0b560da00d47993;hp=1cdc422f82fffbe9248e08afb7c7c3be5ac42c24;hpb=7f76d571fe545578e3bd26e627d181a39a8f1eb7;p=sbcl.git

diff --git a/src/runtime/bsd-os.h b/src/runtime/bsd-os.h
index 1cdc422..7b094c3 100644
--- a/src/runtime/bsd-os.h
+++ b/src/runtime/bsd-os.h
@@ -28,14 +28,10 @@ typedef int os_vm_prot_t;
  * original FreeBSD port of SBCL, that's wrong, it's actually a
  * ucontext_t. */
 typedef ucontext_t os_context_t;
-/* KLUDGE: A hack inherited from CMU CL used to be conditional on
- * !defined(__linux__), and has now been made conditional on
- * CANNOT_GET_TO_SINGLE_STEP_FLAG: if the OS won't let us flip the
- * single-step flag bit in the state stored in a signal context, then
- * we need to mess around with overwriting preceding code with
- * bit-flipping code. This isn't needed in Linux or OpenBSD; I haven't
- * been able to test whether it's still needed in FreeBSD, so for
- * conservatism it's left in. -- WHN 2000-10-24 */
+/* As the sbcl-devel message from Raymond Wiker 2000-12-01, FreeBSD
+ * (unlike Linux and OpenBSD) doesn't let us tweak the CPU's single
+ * step flag bit by messing with the flags stored in a signal context,
+ * so we need to implement single stepping in a more roundabout way. */
 #define CANNOT_GET_TO_SINGLE_STEP_FLAG
 #elif defined __OpenBSD__
 typedef struct sigcontext os_context_t;