diff --git a/Makefile b/Makefile
index 3f81263b26ab2..ad9dcac6bbb7d 100644
--- a/Makefile
+++ b/Makefile
@@ -28,7 +28,7 @@ all: debug release
 # sort is used to remove potential duplicates
 DIRS := $(sort $(build_bindir) $(build_depsbindir) $(build_libdir) $(build_private_libdir) $(build_libexecdir) $(build_includedir) $(build_includedir)/julia $(build_sysconfdir)/julia $(build_datarootdir)/julia $(build_datarootdir)/julia/stdlib $(build_man1dir))
 ifneq ($(BUILDROOT),$(JULIAHOME))
-BUILDDIRS := $(BUILDROOT) $(addprefix $(BUILDROOT)/,base src src/flisp src/support src/clangsa cli doc deps stdlib test test/clangsa test/embedding test/llvmpasses)
+BUILDDIRS := $(BUILDROOT) $(addprefix $(BUILDROOT)/,base src src/flisp src/support src/clangsa cli doc deps stdlib test test/clangsa test/embedding test/gcext test/llvmpasses)
 BUILDDIRMAKE := $(addsuffix /Makefile,$(BUILDDIRS)) $(BUILDROOT)/sysimage.mk
 DIRS += $(BUILDDIRS)
 $(BUILDDIRMAKE): | $(BUILDDIRS)
diff --git a/src/julia_gcext.h b/src/julia_gcext.h
index 6523198474771..669e80d069fa4 100644
--- a/src/julia_gcext.h
+++ b/src/julia_gcext.h
@@ -120,6 +120,8 @@ JL_DLLEXPORT int jl_gc_conservative_gc_support_enabled(void);
 // external allocations may not all be valid objects and that for those,
 // the user *must* validate that they have a proper type, i.e. that
 // jl_typeof(obj) is an actual type object.
+//
+// NOTE: Only valid to call from within a GC context.
 JL_DLLEXPORT jl_value_t *jl_gc_internal_obj_base_ptr(void *p);
 
 // Return a non-null pointer to the start of the stack area if the task
diff --git a/test/gcext/LocalTest.jl b/test/gcext/LocalTest.jl
index f73b4b47e8023..e2ee94e765321 100644
--- a/test/gcext/LocalTest.jl
+++ b/test/gcext/LocalTest.jl
@@ -54,13 +54,13 @@ function set_aux_root(n :: Int, x :: String)
     return ccall(:set_aux_root, Nothing, (UInt, String), n, x)
 end
 
-function internal_obj_scan(p :: Any)
-    if ccall(:internal_obj_scan, Cint, (Any,), p) == 0
-        global internal_obj_scan_failures += 1
-    end
-end
+# function internal_obj_scan(p :: Any)
+#     if ccall(:internal_obj_scan, Cint, (Any,), p) == 0
+#         global internal_obj_scan_failures += 1
+#     end
+# end
 
-global internal_obj_scan_failures = 0
+# global internal_obj_scan_failures = 0
 
 for i in 0:1000
     set_aux_root(i, string(i))
@@ -70,12 +70,12 @@ function test()
     local stack = make()
     for i in 1:100000
         push(stack, string(i, base=2))
-        internal_obj_scan(top(stack))
+        # internal_obj_scan(top(stack))
     end
     for i in 1:1000
         local stack2 = make()
-        internal_obj_scan(stack2)
-        internal_obj_scan(blob(stack2))
+        # internal_obj_scan(stack2)
+        # internal_obj_scan(blob(stack2))
         while !empty(stack)
             push(stack2, pop(stack))
         end
@@ -98,5 +98,5 @@ end
 print(gc_counter_full(), " full collections.\n")
 print(gc_counter_inc(), " partial collections.\n")
 print(num_obj_sweeps(), " object sweeps.\n")
-print(internal_obj_scan_failures, " internal object scan failures.\n")
+# print(internal_obj_scan_failures, " internal object scan failures.\n")
 print(corrupted_roots, " corrupted auxiliary roots.\n")
diff --git a/test/gcext/Makefile b/test/gcext/Makefile
index 7cb602572e3c5..b3314d1f9b32b 100644
--- a/test/gcext/Makefile
+++ b/test/gcext/Makefile
@@ -41,7 +41,7 @@ $(BIN)/gcext-debug$(EXE): $(SRCDIR)/gcext.c
 ifneq ($(abspath $(BIN)),$(abspath $(SRCDIR)))
 # for demonstration purposes, our demo code is also installed
 # in $BIN, although this would likely not be typical
-$(BIN)/LocalModule.jl: $(SRCDIR)/LocalModule.jl
+$(BIN)/LocalTest.jl: $(SRCDIR)/LocalTest.jl
 	cp $< $@
 endif
 
diff --git a/test/gcext/gcext-test.jl b/test/gcext/gcext-test.jl
index e6f3e3663ff0e..0dc9bbadd92b5 100644
--- a/test/gcext/gcext-test.jl
+++ b/test/gcext/gcext-test.jl
@@ -31,12 +31,15 @@ end
     errlines = fetch(err_task)
     lines = fetch(out_task)
     @test length(errlines) == 0
-    @test length(lines) == 6
+    # @test length(lines) == 6
+    @test length(lines) == 5
     @test checknum(lines[2], r"([0-9]+) full collections", n -> n >= 10)
     @test checknum(lines[3], r"([0-9]+) partial collections", n -> n > 0)
     @test checknum(lines[4], r"([0-9]+) object sweeps", n -> n > 0)
-    @test checknum(lines[5], r"([0-9]+) internal object scan failures",
-        n -> n == 0)
-    @test checknum(lines[6], r"([0-9]+) corrupted auxiliary roots",
+    # @test checknum(lines[5], r"([0-9]+) internal object scan failures",
+    #     n -> n == 0)
+    # @test checknum(lines[6], r"([0-9]+) corrupted auxiliary roots",
+    #    n -> n == 0)
+    @test checknum(lines[5], r"([0-9]+) corrupted auxiliary roots",
         n -> n == 0)
 end
diff --git a/test/gcext/gcext.c b/test/gcext/gcext.c
index 7f2986d8f1f57..842d6004ab965 100644
--- a/test/gcext/gcext.c
+++ b/test/gcext/gcext.c
@@ -307,6 +307,7 @@ static size_t gc_alloc_size(jl_value_t *val)
 
 int internal_obj_scan(jl_value_t *val)
 {
+    // FIXME: `jl_gc_internal_obj_base_ptr` is not allowed to be called from outside GC
     if (jl_gc_internal_obj_base_ptr(val) == val) {
         size_t size = gc_alloc_size(val);
         char *addr = (char *)val;