Unhide source context since it sometimes contains critical information

Author: Jameson Ernst

compiler/rustc.vim

@@ -39,8 +39,7 @@ CompilerSet errorformat+=
 			\%Eerror[E%n]:\ %m,
 			\%Wwarning:\ %m,
 			\%Inote:\ %m,
-			\%C\ %#-->\ %f:%l:%c,
-			\%C%*[0-9\ ]\|%.%#
+			\%C\ %#-->\ %f:%l:%c
 
 let &cpo = s:cpo_save
 unlet s:cpo_save

syntax_checkers/rust/rustc.vim

@@ -32,8 +32,7 @@ function! SyntaxCheckers_rust_rustc_GetLocList() dict
         \ '%Eerror[E%n]: %m,' .
         \ '%Wwarning: %m,' .
         \ '%Inote: %m,' .
-        \ '%C %#--> %f:%l:%c,' .
-        \ '%C%*[0-9 ]|%.%#'
+        \ '%C %#--> %f:%l:%c'
 
     return SyntasticMake({
         \ 'makeprg': makeprg,