diff --git a/compat/win32/fscache.c b/compat/win32/fscache.c
index d42ff66ba5106e..313361867414ed 100644
--- a/compat/win32/fscache.c
+++ b/compat/win32/fscache.c
@@ -2,6 +2,7 @@
 #include "../../hashmap.h"
 #include "../win32.h"
 #include "fscache.h"
+#include "config.h"
 
 static int initialized;
 static volatile long enabled;
@@ -353,7 +354,11 @@ int fscache_enable(int enable)
 	int result;
 
 	if (!initialized) {
+		int fscache = git_env_bool("GIT_TEST_FSCACHE", -1);
+
 		/* allow the cache to be disabled entirely */
+		if (fscache != -1)
+			core_fscache = fscache;
 		if (!core_fscache)
 			return 0;
 
diff --git a/t/README b/t/README
index 1326fd7505fde3..d11e8acfaedb27 100644
--- a/t/README
+++ b/t/README
@@ -392,6 +392,9 @@ GIT_TEST_SIDEBAND_ALL=<boolean>, when true, overrides the
 fetch-pack to not request sideband-all (even if the server advertises
 sideband-all).
 
+GIT_TEST_FSCACHE=<boolean> exercises the uncommon fscache code path
+which adds a cache below mingw's lstat and dirent implementations.
+
 Naming Tests
 ------------