Fix logic in exec_file_locate_attach

This commit fixes an error in exec_file_locate_attach where
the main executable could be loaded from outside the sysroot
if a nonempty, non-"target:" sysroot was set but the discovered
executable filename did not exist in that sysroot and did exist
on the main filesystem.

gdb/ChangeLog:

	* exec.c (exec_file_locate_attach): Do not attempt to
	locate main executable locally if not found in sysroot.

gdb/testsuite/ChangeLog:

	* gdb.base/attach-pie-noexec.exp: Do not expect an error
	message on attach.

1 files changed, 6 insertions, 3 deletions

diff --git a/gdb/exec.c b/gdb/exec.c
index 0b8c077..90811c0 100644
--- a/gdb/exec.c
+++ b/gdb/exec.c
@@ -156,9 +156,12 @@ exec_file_locate_attach (int pid, int from_tty)
   /* If gdb_sysroot is not empty and the discovered filename
      is absolute then prefix the filename with gdb_sysroot.  */
   if (*gdb_sysroot != '\0' && IS_ABSOLUTE_PATH (exec_file))
-    full_exec_path = exec_file_find (exec_file, NULL);
-
-  if (full_exec_path == NULL)
+    {
+      full_exec_path = exec_file_find (exec_file, NULL);
+      if (full_exec_path == NULL)
+	return;
+    }
+  else
     {
       /* It's possible we don't have a full path, but rather just a
 	 filename.  Some targets, such as HP-UX, don't provide the