commit cae24be4a808d60313913cc6feea6c2bee2e2a42
author Bram Moolenaar <Bram@vim.org> Mon Jul 10 22:12:10 2017 +0200
committer Bram Moolenaar <Bram@vim.org> Mon Jul 10 22:12:10 2017 +0200
tree 5759bd8d564c2160ac7ab204cc3da7cc9ed32ba9
parent 163095f088a7c29710a16c75bb56229dd3b4116a

patch 8.0.0705: crash when there is an error in a timer callback

Problem:    Crash when there is an error in a timer callback. (Aron Griffis,
            Ozaki Kiichi)
Solution:   Check did_throw before discarding an exception.  NULLify
            current_exception when no longer valid.

src/ex_cmds2.c

diff --git a/src/ex_cmds2.c b/src/ex_cmds2.c
index 76e62f7..5f19592 100644
--- a/src/ex_cmds2.c
+++ b/src/ex_cmds2.c
@@ -1235,7 +1235,7 @@
 	    if (called_emsg)
 	    {
 		++timer->tr_emsg_count;
-		if (!did_throw_save && current_exception != NULL)
+		if (!did_throw_save && did_throw && current_exception != NULL)
 		    discard_current_exception();
 	    }
 	    did_emsg = did_emsg_save;