Fix GCExt test (JuliaLang#47699)

* Add test/gcext to out-of-tree
* Disable gcext test that uses jl_gc_internal_obj_base_ptr

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)

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

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")

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
 

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

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;