Fix DARWIN_OS_CASE_SENSITIVE_FIXME==2 false alarm

* src/fileio.c (file_name_case_insensitive_p):
Don’t compile the (DARWIN_OS_CASE_SENSITIVE_FIXME == 2)
code unless DARWIN_OS_CASE_SENSITIVE_FIXME is 2.
Problem reported by Philipp Stephani in:
http://lists.gnu.org/archive/html/emacs-devel/2017-05/msg00495.html

1 files changed, 7 insertions, 2 deletions

diff --git a/src/fileio.c b/src/fileio.c
index acbf76e0d81..e5e350542f9 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -2294,10 +2294,14 @@ file_name_case_insensitive_p (const char *filename)
                       & VOL_CAP_FMT_CASE_SENSITIVE);
         }
     }
-  else if (DARWIN_OS_CASE_SENSITIVE_FIXME == 2)
+# if DARWIN_OS_CASE_SENSITIVE_FIXME == 2
     {
       /* The following is based on
-         http://lists.apple.com/archives/darwin-dev/2007/Apr/msg00010.html.  */
+         http://lists.apple.com/archives/darwin-dev/2007/Apr/msg00010.html.
+         It is normally not even compiled, since it runs afoul of
+         static checking.  See:
+         http://lists.gnu.org/archive/html/emacs-devel/2017-05/msg00495.html
+         */
       struct attrlist alist;
       unsigned char buffer[sizeof (vol_capabilities_attr_t) + sizeof (size_t)];
 
@@ -2309,6 +2313,7 @@ file_name_case_insensitive_p (const char *filename)
       vol_capabilities_attr_t *vcaps = buffer;
       return !(vcaps->capabilities[0] & VOL_CAP_FMT_CASE_SENSITIVE);
     }
+# endif
 #endif  /* DARWIN_OS */
 
 #if defined CYGWIN || defined DOS_NT