diff mbox

[4/6] x32: gdbserver's agent bytecode JIT: fix "call" emission

Message ID 1469667685-10848-5-git-send-email-palves@redhat.com
State New, archived
Headers

Commit Message

Pedro Alves July 28, 2016, 1:01 a.m. UTC 
  Running fast tracepoint tests on x32 exposes a latent bug in the agent
bytecode jitting.  There's a code path that forgets to emit the call
opcode...  Whoops.  Fixes a bunch of gdb.trace/trace-condition.exp
FAILs, like:

  (gdb)
  continue
  Continuing.

  Thread 1 "trace-condition" received signal SIGSEGV, Segmentation fault.
  0x7ffec016 in ?? ()
  (gdb) FAIL: gdb.trace/trace-condition.exp: ftrace: $rip == *set_point: advance through tracing

gdb/gdbserver/ChangeLog:
yyyy-mm-dd  Pedro Alves  <palves@redhat.com>

	* linux-x86-low.c (amd64_emit_call): Emit missing call opcode.
---
 gdb/gdbserver/linux-x86-low.c | 2 ++
 1 file changed, 2 insertions(+)
diff mbox

Patch

diff --git a/gdb/gdbserver/linux-x86-low.c b/gdb/gdbserver/linux-x86-low.c
index 1ba98ba..d847b93 100644
--- a/gdb/gdbserver/linux-x86-low.c
+++ b/gdb/gdbserver/linux-x86-low.c
@@ -1842,6 +1842,8 @@  amd64_emit_call (CORE_ADDR fn)
   else
     {
       int offset32 = offset64; /* we know we can't overflow here.  */
+
+      buf[i++] = 0xe8; /* call <reladdr> */
       memcpy (buf + i, &offset32, 4);
       i += 4;
     }