diff --git a/winsup/utils/Makefile.in b/winsup/utils/Makefile.in
index 01d2f3062..e4f55dd3c 100644
--- a/winsup/utils/Makefile.in
+++ b/winsup/utils/Makefile.in
@@ -124,7 +124,7 @@ MINGW_BINS += testsuite.exe
 MINGW_OBJS += path-testsuite.o testsuite.o
 testsuite.exe: path-testsuite.o
 path-testsuite.cc: path.cc ; @test -L $@ || ln -sf ${filter %.cc,$^} $@
-path-testsuite.o: MINGW_CXXFLAGS += -DTESTSUITE -Wno-error=write-strings
+path-testsuite.o: MINGW_CXXFLAGS += -DTESTSUITE
 # this is necessary because this .c lives in the build dir instead of src
 path-testsuite.o: MINGW_CXXFLAGS += -I$(srcdir)
 path-testsuite.cc path.cc testsuite.cc: testsuite.h
diff --git a/winsup/utils/path.cc b/winsup/utils/path.cc
index 4c1bb4029..29344be02 100644
--- a/winsup/utils/path.cc
+++ b/winsup/utils/path.cc
@@ -559,6 +559,7 @@ from_fstab (bool user, PWCHAR path, PWCHAR path_end)
 
 #ifndef FSTAB_ONLY
 
+#ifndef TESTSUITE
 static int
 mnt_sort (const void *a, const void *b)
 {
@@ -580,9 +581,6 @@ extern "C" WCHAR cygwin_dll_path[];
 static void
 read_mounts ()
 {
-/* If TESTSUITE is defined, bypass this whole function as a harness
-   mount table will be provided.  */
-#ifndef TESTSUITE
   HKEY setup_key;
   LONG ret;
   DWORD len;
@@ -654,8 +652,8 @@ read_mounts ()
   from_fstab (false, path, path_end);
   from_fstab (true, path, path_end);
   qsort (mount_table, max_mount_entry, sizeof (mnt_t), mnt_sort);
-#endif /* !defined(TESTSUITE) */
 }
+#endif /* !defined(TESTSUITE) */
 
 /* Return non-zero if PATH1 is a prefix of PATH2.
    Both are assumed to be of the same path style and / vs \ usage.
diff --git a/winsup/utils/testsuite.cc b/winsup/utils/testsuite.cc
index c0a800b01..23ed8e0d8 100644
--- a/winsup/utils/testsuite.cc
+++ b/winsup/utils/testsuite.cc
@@ -15,7 +15,9 @@ details. */
 #include <unistd.h>
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
+#ifndef TESTSUITE
 #define TESTSUITE
+#endif
 #include "testsuite.h"
 
 typedef struct
diff --git a/winsup/utils/testsuite.h b/winsup/utils/testsuite.h
index d0a47b23a..0dd631539 100644
--- a/winsup/utils/testsuite.h
+++ b/winsup/utils/testsuite.h
@@ -30,12 +30,12 @@ details. */
 #if defined(TESTSUITE_MOUNT_TABLE)
 static mnt_t mount_table[] = {
 /* native                 posix               flags */
- { TESTSUITE_ROOT,        (char*)"/",                MOUNT_SYSTEM},
- { "O:\\other",           (char*)"/otherdir",        MOUNT_SYSTEM},
- { "S:\\some\\dir",       (char*)"/somedir",         MOUNT_SYSTEM},
- { TESTSUITE_ROOT"\\bin", (char*)"/usr/bin",         MOUNT_SYSTEM},
- { TESTSUITE_ROOT"\\lib", (char*)"/usr/lib",         MOUNT_SYSTEM},
- { ".",                   (char*)TESTSUITE_CYGDRIVE, MOUNT_SYSTEM | MOUNT_CYGDRIVE},
+ { (char*)TESTSUITE_ROOT,        (char*)"/",                MOUNT_SYSTEM},
+ { (char*)"O:\\other",           (char*)"/otherdir",        MOUNT_SYSTEM},
+ { (char*)"S:\\some\\dir",       (char*)"/somedir",         MOUNT_SYSTEM},
+ { (char*)TESTSUITE_ROOT"\\bin", (char*)"/usr/bin",         MOUNT_SYSTEM},
+ { (char*)TESTSUITE_ROOT"\\lib", (char*)"/usr/lib",         MOUNT_SYSTEM},
+ { (char*)".",                   (char*)TESTSUITE_CYGDRIVE, MOUNT_SYSTEM | MOUNT_CYGDRIVE},
  { NULL,                  (char*)NULL,               0}
 };