From da365134b537b00966ba6de1b6184e9fd76e4733 Mon Sep 17 00:00:00 2001
From: w0rp <devw0rp@gmail.com>
Date: Wed, 25 Oct 2017 23:43:09 +0100
Subject: [PATCH] Fix an exception with notes with no previous message

---
 autoload/ale/handlers/gcc.vim       | 8 ++++++--
 test/handler/test_gcc_handler.vader | 8 ++++++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/autoload/ale/handlers/gcc.vim b/autoload/ale/handlers/gcc.vim
index a3f2a302..b7db09eb 100644
--- a/autoload/ale/handlers/gcc.vim
+++ b/autoload/ale/handlers/gcc.vim
@@ -82,8 +82,12 @@ function! ale#handlers#gcc#HandleGCCFormat(buffer, lines) abort
             " If the 'error type' is a note, make it detail related to
             " the previous error parsed in output
             if l:match[4] is# 'note'
-                let l:output[-1]['detail'] = get(l:output[-1], 'detail', '')
-                            \    . s:RemoveUnicodeQuotes(l:match[0]) . "\n"
+                if !empty(l:output)
+                    let l:output[-1]['detail'] =
+                    \   get(l:output[-1], 'detail', '')
+                    \   . s:RemoveUnicodeQuotes(l:match[0]) . "\n"
+                endif
+
                 continue
             endif
 
diff --git a/test/handler/test_gcc_handler.vader b/test/handler/test_gcc_handler.vader
index be9e90ee..321dbc6e 100644
--- a/test/handler/test_gcc_handler.vader
+++ b/test/handler/test_gcc_handler.vader
@@ -128,3 +128,11 @@ Execute(The GCC handler should handle syntax errors):
   \ '<stdin>:4: error: ''cat'' was not declared in this scope',
   \ '<stdin>:12: error: expected `;'' before ''o''',
   \ ])
+
+Execute(The GCC handler should handle notes with no previous message):
+  AssertEqual
+  \ [],
+  \ ale#handlers#gcc#HandleGCCFormat(347, [
+  \   '<stdin>:1:1: note: x',
+  \   '<stdin>:1:1: note: x',
+  \ ])