DTrace: Revert r249367

The following change from illumos brought caused DTrace to
pause in an interactive environment:

3026 libdtrace should set LD_NOLAZYLOAD=1 to help the pid provider

This was not detected during testing because it doesn't
affect scripts.

We shouldn't be changing the environment, especially since the
LD_NOLAZYLOAD option doesn't apply to our (GNU) ld.
Unfortunately the change from upstream was made in such a way
that it is very difficult to separate this change from the
others so, at least for now, it's better to just revert
everything.

Reference:
https://www.illumos.org/issues/3026

Reported by:	Navdeep Parhar and Mark Johnston

1 files changed, 1 insertions, 6 deletions

diff --git a/cddl/contrib/opensolaris/lib/libdtrace/i386/dt_isadep.c b/cddl/contrib/opensolaris/lib/libdtrace/i386/dt_isadep.c
index 9479e83..f11ae48 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/i386/dt_isadep.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/i386/dt_isadep.c
@@ -24,10 +24,6 @@
  * Use is subject to license terms.
  */
 
-/*
- * Copyright (c) 2012 by Delphix. All rights reserved.
- */
-
 #include <stdlib.h>
 #include <assert.h>
 #include <errno.h>
@@ -529,8 +525,7 @@ dt_instr_size(uchar_t *instr, dtrace_hdl_t *dtp, pid_t pid, uintptr_t addr,
 	 * another debugger attached to this process. The original instruction
 	 * can't be recovered so this must fail.
 	 */
-	if (x86dis.d86_len == 1 &&
-	    (uchar_t)x86dis.d86_bytes[0] == FASTTRAP_INSTR)
+	if (x86dis.d86_len == 1 && instr[0] == FASTTRAP_INSTR)
 		return (-1);
 
 	return (x86dis.d86_len);