0.7.7.17:

        MIPS fixup
        ... Linux appears to put garbage in the sc_cause sigcontext
                slot.  So assume that we never trap in a branch delay
                instruction, and hope for the best.

diff --git a/NEWS b/NEWS
index c08fbb8..59bd7fb 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -1251,6 +1251,10 @@ changes in sbcl-0.7.7 relative to sbcl-0.7.6:
     bug fix involving the names of PCL MAKE-INSTANCE functions)
 
 changes in sbcl-0.7.8 relative to sbcl-0.7.7:
+  * A beta-quality port to the mips architecture running Linux,
+    based on the old CMUCL backend, has been made.  It has been tested
+    on a big-endian kernel, and works sufficiently well to be able to
+    rebuild itself; it has not been tested in little-endian mode.
   * fixed bug 120a: The compiler now deals correctly with IFs where
     the consequent is the same as the alternative, instead of
     misderiving the return type. (thanks to Alexey Dejneka)

diff --git a/src/runtime/mips-arch.c b/src/runtime/mips-arch.c
index a65a381..7b68e65 100644 (file)
--- a/src/runtime/mips-arch.c
+++ b/src/runtime/mips-arch.c
@@ -106,10 +106,18 @@ emulate_branch(os_context_t *context, unsigned long inst)
 void arch_skip_instruction(os_context_t *context)
 {
     /* Skip the offending instruction */
-    if (os_context_bd_cause(context))
+    if (os_context_bd_cause(context)) {
+       /* Currently, we never get here, because Linux' support for
+           bd_cause seems not terribly solid (c.f os_context_bd_cause
+           in mips-linux-os.c).  If a port to Irix comes along, this
+           code will be executed, because presumably Irix' support is
+           better (it can hardly be worse).  We lose() to remind the
+           porter to review this code.  -- CSR, 2002-09-06 */
+       lose("bd_cause branch taken; review code for new OS?\n");
         *os_context_pc_addr(context) = 
            emulate_branch(context, 
                           *(unsigned long *) *os_context_pc_addr(context));
+    }
     else
         *os_context_pc_addr(context) += 4;
 

diff --git a/src/runtime/mips-linux-os.c b/src/runtime/mips-linux-os.c
index f92a232..e9d9803 100644 (file)
--- a/src/runtime/mips-linux-os.c
+++ b/src/runtime/mips-linux-os.c
@@ -83,8 +83,17 @@ os_context_bd_cause(os_context_t *context)
 {
     /* We need to see if whatever happened, happened because of a
        branch delay event */
-    return (((struct sigcontext *) &(context->uc_mcontext))->sc_cause 
-           & CAUSEF_BD);
+    /* FIXME: However, I'm not convinced that the values that Linux
+       puts in this slot are actually right; specifically, attempting
+       to compile sbcl with sbcl-0.7.7.7 lead to an "infinite SIGTRAP
+       loop" where a (BREAK 16) not in a branch delay slot would have
+       CAUSEF_BD filled. So, we comment
+
+        return (((struct sigcontext *) &(context->uc_mcontext))->sc_cause 
+               & CAUSEF_BD);
+
+       out and return 0 always.  -- CSR, 2002-09-02 */
+    return 0;
 }
 
 void 

diff --git a/version.lisp-expr b/version.lisp-expr
index b10b5b7..fdd0192 100644 (file)
--- a/version.lisp-expr
+++ b/version.lisp-expr
@@ -18,4 +18,4 @@
 ;;; for internal versions, especially for internal versions off the
 ;;; main CVS branch, it gets hairier, e.g. "0.pre7.14.flaky4.13".)
 
-"0.7.7.16"
+"0.7.7.17"