From 69ea553024155638c89bc12dca648c87a625ab5f Mon Sep 17 00:00:00 2001
From: Mike Pall <mike>
Date: Mon, 1 Mar 2010 06:33:48 +0100
Subject: [PATCH] Fix pc to line number translation for GDB JIT API.

---
 src/lj_gdbjit.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/lj_gdbjit.c b/src/lj_gdbjit.c
index c6e34807..951d52ec 100644
--- a/src/lj_gdbjit.c
+++ b/src/lj_gdbjit.c
@@ -711,7 +711,10 @@ void lj_gdbjit_addtrace(jit_State *J, Trace *T, TraceNo traceno)
   ctx.szmcode = T->szmcode;
   ctx.spadjp = CFRAME_SIZE_JIT + (MSize)(parent?J->trace[parent]->spadjust:0);
   ctx.spadj = CFRAME_SIZE_JIT + T->spadjust;
-  ctx.lineno = proto_line(pt, proto_bcpos(pt, startpc));
+  if (startpc >= proto_bc(pt) && startpc < proto_bc(pt) + pt->sizebc)
+    ctx.lineno = proto_line(pt, proto_bcpos(pt, startpc));
+  else
+    ctx.lineno = proto_line(pt, 0);  /* Wrong, but better than nothing. */
   ctx.filename = strdata(proto_chunkname(pt));
   if (*ctx.filename == '@' || *ctx.filename == '=')
     ctx.filename++;