dir.c: make add_excludes aware of fscache during status

compat/win32/fscache.c

@@ -9,6 +9,11 @@ static struct hashmap map;
 static CRITICAL_SECTION mutex;
 static struct trace_key trace_fscache = TRACE_KEY_INIT(FSCACHE);
 
+int fscache_is_enabled(void)
+{
+	return enabled;
+}
+
 /*
  * An entry in the file system cache. Used for both entire directory listings
  * and file entries.

compat/win32/fscache.h

@@ -4,6 +4,9 @@
 int fscache_enable(int enable);
 #define enable_fscache(x) fscache_enable(x)
 
+int fscache_is_enabled(void);
+#define is_fscache_enabled() (fscache_is_enabled())
+
 DIR *fscache_opendir(const char *dir);
 int fscache_lstat(const char *file_name, struct stat *buf);
 

dir.c

@@ -758,12 +758,27 @@ static int add_excludes(const char *fname, const char *base, int baselen,
 	size_t size = 0;
 	char *buf, *entry;
 
-	fd = open(fname, O_RDONLY);
-	if (fd < 0 || fstat(fd, &st) < 0) {
-		if (fd < 0)
-			warn_on_fopen_errors(fname);
-		else
-			close(fd);
+	if (is_fscache_enabled()) {
+		if (lstat(fname, &st) < 0) {
+			fd = -1;
+		} else {
+			fd = open(fname, O_RDONLY);
+			if (fd < 0)
+				warn_on_fopen_errors(fname);
+		}
+	} else {
+		fd = open(fname, O_RDONLY);
+		if (fd < 0 || fstat(fd, &st) < 0) {
+			if (fd < 0)
+				warn_on_fopen_errors(fname);
+			else {
+				close(fd);
+				fd = -1;
+			}
+		}
+	}
+
+	if (fd < 0) {
 		if (!istate ||
 		    (buf = read_skip_worktree_file_from_index(istate, fname, &size, sha1_stat)) == NULL)
 			return -1;

git-compat-util.h

@@ -1255,6 +1255,10 @@ static inline int is_missing_file_error(int errno_)
 #define enable_fscache(x) /* noop */
 #endif
 
+#ifndef is_fscache_enabled
+#define is_fscache_enabled() (0)
+#endif
+
 extern int cmd_main(int, const char **);
 
 /*