patch 7.4.1008
Problem:    The OS/2 code pollutes the source while nobody uses it these days.
Solution:   Drop the support for OS/2.
diff --git a/src/misc2.c b/src/misc2.c
index beb3d46..f13a80e 100644
--- a/src/misc2.c
+++ b/src/misc2.c
@@ -5521,7 +5521,7 @@
     if (vim_isAbsName(ff_file_to_find)
 	    /* "..", "../path", "." and "./path": don't use the path_option */
 	    || rel_to_curdir
-#if defined(MSWIN) || defined(MSDOS) || defined(OS2)
+#if defined(MSWIN) || defined(MSDOS)
 	    /* handle "\tmp" as absolute path */
 	    || vim_ispathsep(ff_file_to_find[0])
 	    /* handle "c:name" as absolute path */