diff --git a/src/test/run-make-fulldeps/tools.mk b/src/test/run-make-fulldeps/tools.mk
index 79399281804f..4b9ab0b7c23d 100644
--- a/src/test/run-make-fulldeps/tools.mk
+++ b/src/test/run-make-fulldeps/tools.mk
@@ -47,6 +47,7 @@ DYLIB = $(TMPDIR)/$(1).dll
 STATICLIB = $(TMPDIR)/$(1).lib
 STATICLIB_GLOB = $(1)*.lib
 BIN = $(1).exe
+LLVM_FILECHECK := $(shell cygpath -u "$(LLVM_FILECHECK)")
 else
 RUN = $(TARGET_RPATH_ENV) $(RUN_BINFILE)
 FAIL = $(TARGET_RPATH_ENV) $(RUN_BINFILE) && exit 1 || exit 0
diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs
index 9db16b69e5f2..0dff218d88ae 100644
--- a/src/tools/compiletest/src/runtest.rs
+++ b/src/tools/compiletest/src/runtest.rs
@@ -2691,6 +2691,10 @@ impl<'test> TestCx<'test> {
             cmd.env("CLANG", clang);
         }
 
+        if let Some(ref filecheck) = self.config.llvm_filecheck {
+            cmd.env("LLVM_FILECHECK", filecheck);
+        }
+
         // We don't want RUSTFLAGS set from the outside to interfere with
         // compiler flags set in the test cases:
         cmd.env_remove("RUSTFLAGS");