ctf_xfer_partial: Return TARGET_XFER_E_IO instead of -1 on error

Use the enum value instead of the corresponding int value.

gdb/ChangeLog:

	* ctf.c (ctf_xfer_partial): Return TARGET_XFER_E_IO instead of
	-1 on error.

2 files changed, 6 insertions, 1 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index a481f09..a063a04 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2015-10-26  Simon Marchi  <simon.marchi@polymtl.ca>
+
+	* ctf.c (ctf_xfer_partial): Return TARGET_XFER_E_IO instead of
+	-1 on error.
+
 2015-10-26  Doug Evans  <dje@google.com>
 
 	PR symtab/17391
diff --git a/gdb/ctf.c b/gdb/ctf.c
index 6c1aede..dc378d1 100644
--- a/gdb/ctf.c
+++ b/gdb/ctf.c
@@ -1273,7 +1273,7 @@ ctf_xfer_partial (struct target_ops *ops, enum target_object object,
 {
   /* We're only doing regular memory for now.  */
   if (object != TARGET_OBJECT_MEMORY)
-    return -1;
+    return TARGET_XFER_E_IO;
 
   if (readbuf == NULL)
     error (_("ctf_xfer_partial: trace file is read-only"));