diff --git a/runtime/syntax/c.vim b/runtime/syntax/c.vim
index 9456212..a0b94ae 100644
--- a/runtime/syntax/c.vim
+++ b/runtime/syntax/c.vim
@@ -270,7 +270,7 @@
 endif
 
 " Accept %: for # (C99)
-syn region	cPreCondit	start="^\s*\(%:\|#\)\s*\(if\|ifdef\|ifndef\|elif\)\>" skip="\\$" end="$"  contains=cComment,cCommentL,cCppString,cCharacter,cCppParen,cParenError,cNumbers,cCommentError,cSpaceError
+syn region      cPreCondit      start="^\s*\(%:\|#\)\s*\(if\|ifdef\|ifndef\|elif\)\>" skip="\\$" end="$"  keepend contains=cComment,cCommentL,cCppString,cCharacter,cCppParen,cParenError,cNumbers,cCommentError,cSpaceError
 syn match	cPreCondit	display "^\s*\(%:\|#\)\s*\(else\|endif\)\>"
 if !exists("c_no_if0")
   if !exists("c_no_if0_fold")