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 #

 # This Source Code Form is subject to the terms of the Mozilla Public

 # License, v. 2.0. If a copy of the MPL was not distributed with this

 # file, You can obtain one at http://mozilla.org/MPL/2.0/.

 DIST_INSTALL = 1

 # For FORCE_SHARED_LIB

 include $(topsrcdir)/config/config.mk

 ifneq (1_1,$(MOZ_MEMORY)_$(or $(MOZ_NATIVE_JEMALLOC),$(FORCE_SHARED_LIB)))

 ifneq (,$(filter WINNT,$(OS_ARCH)))

 SDK_LIBRARY = $(IMPORT_LIBRARY)

 else

 ifdef FORCE_SHARED_LIB

 SDK_LIBRARY = $(SHARED_LIBRARY)

 else

 SDK_LIBRARY = $(REAL_LIBRARY)

 endif

 endif

 endif

 MOZ_GLUE_LDFLAGS = # Don't link against ourselves

 SHARED_LIBRARY_LIBS += $(call EXPAND_LIBNAME_PATH,mfbt,$(DEPTH)/mfbt)

 ifneq (,$(ZLIB_IN_MOZGLUE)$(MOZ_LINKER))

 ifdef MOZ_NATIVE_ZLIB

 EXTRA_DSO_LDOPTS += $(MOZ_ZLIB_LIBS)

 else

 SHARED_LIBRARY_LIBS += $(MOZ_ZLIB_LIBS)

 endif

 endif

 ifeq (WINNT,$(OS_TARGET))

 mozglue.def: mozglue.def.in

 	$(call py_action,preprocessor,$(if $(MOZ_REPLACE_MALLOC),-DMOZ_REPLACE_MALLOC) $(ACDEFINES) $< -o $@)

 GARBAGE += mozglue.def

 ifneq (,$(filter -DEFAULTLIB:mozcrt,$(MOZ_GLUE_LDFLAGS)))

 # Don't install the import library if we use mozcrt

 NO_INSTALL_IMPORT_LIBRARY = 1

 endif

 EXTRA_DSO_LDOPTS += \

 	$(call EXPAND_LIBNAME,version) \

 	$(NULL)

 endif

 ifeq (Darwin_1,$(OS_TARGET)_$(MOZ_REPLACE_MALLOC))

 EXTRA_DSO_LDOPTS += \

   -Wl,-U,_replace_init \

   -Wl,-U,_replace_malloc \

   -Wl,-U,_replace_posix_memalign \

   -Wl,-U,_replace_aligned_alloc \

   -Wl,-U,_replace_calloc \

   -Wl,-U,_replace_realloc \

   -Wl,-U,_replace_free \

   -Wl,-U,_replace_memalign \

   -Wl,-U,_replace_valloc \

   -Wl,-U,_replace_malloc_usable_size \

   -Wl,-U,_replace_malloc_good_size \

   -Wl,-U,_replace_jemalloc_stats \

   -Wl,-U,_replace_jemalloc_purge_freed_pages \

   -Wl,-U,_replace_jemalloc_free_dirty_pages \

   $(NULL)

 ifneq ($(MOZ_REPLACE_MALLOC_LINKAGE),compiler support)

 EXTRA_DSO_LDOPTS += -flat_namespace

 endif

 ifeq ($(MOZ_REPLACE_MALLOC_LINKAGE),dummy library)

 EXTRA_DSO_LDOPTS += -Wl,-weak_library,$(DEPTH)/memory/replace/dummy/$(DLL_PREFIX)replace_malloc$(DLL_SUFFIX)

 endif

 endif

 ifeq (android, $(MOZ_WIDGET_TOOLKIT))

 # To properly wrap jemalloc's pthread_atfork call.

 EXTRA_DSO_LDOPTS += -Wl,--wrap=pthread_atfork

 endif

 ifdef MOZ_LINKER

 ifeq (arm, $(TARGET_CPU))

 EXTRA_DSO_LDOPTS += -Wl,-version-script,$(srcdir)/arm-eabi-filter

 endif

 endif

 ifeq (Android, $(OS_TARGET))

 WRAP_LDFLAGS := $(filter -Wl%,$(WRAP_LDFLAGS))

 endif

 include $(topsrcdir)/config/rules.mk

 ifdef MOZ_MEMORY

 ifeq (WINNT,$(OS_TARGET))

 # Roll our own custom logic here for the import library

 ###############################################################################

 #

 # Linking Mozilla itself to jemalloc is not particularly difficult.  To do this

 # we avoid linking directly to the Microsoft-provided CRT import libraries.

 # Instead, we link to our own import library which we generate here.  To

 # replace the CRT's malloc/free/other memory management symbols we export

 # our own versions out of jemalloc.dll.  We then take the import library that

 # the compiler generates for jemalloc.dll and combine it with the MS CRT import

 # libraries.  We put our library on the command line first, and the CRT symbols

 # are discarded in favor of our versions!

 #

 # Unfortunately that was too easy.  The CRT import library is not a standard

 # import library that contains a list of symbols and whatnot.  It also includes

 # object files that are linked into generated programs.  One of these,

 # crtdll.obj is (as one might expect) linked into all DLLs that link against

 # the CRT.  This file does things like run static C++ constructors when the

 # DLL is attached, call DllMain, etc.

 #

 # In the CRT source all malloc/free calls are made to malloc_crt and free_crt.

 # In debug builds these are both defined to malloc_dbg and free_dbg.  In opt

 # builds malloc_crt is an actual function, implemented and exposed from the

 # CRT.  free_crt is, however, defined to be just plain old free.  This works

 # fine inside the CRT where malloc_crt and free operate on the same heap.

 # Outside the CRT malloc_crt is in the CRT's heap, but free is in jemalloc's

 # heap.  This causes much pain at shutdown :-(

 #

 # The obvious solution here is to override malloc_crt too.  Unfortunately,

 # that doesn't work because the CRT expects to be able to call msize on this

 # piece of memory deep inside the CRT, which will fail because it'll call the

 # CRT's msize on a pointer in jemalloc's heap.

 #

 # Our solution to this is quite devious.  We take apart the CRT's import lib

 # and remove the problematic object file.  We then poke at the object file's

 # symbol table and replace '__imp__free' (which means grab free from some

 # other DLL) with '__imp__frex'.  Then we define our own dummy no-op function

 # in jemalloc.dll and export it as frex.  Then we put the CRT import lib

 # back together with the patched crtdll.obj, glue it to the end of jemalloc's

 # import library and link the rest of Mozilla to that.

 #

 # The result?  A binary that uses jemalloc, doesn't crash, and leaks a tiny

 # amount of memory (32 words per DLL in the 2010 CRT) at shutdown.

 #

 ###############################################################################

 libs:: mozcrt.lib

 	$(INSTALL) $(IFLAGS2) mozcrt.lib $(DIST)/lib

 # And finally combine that with the jemalloc import library to get an import

 # library that has our malloc/free/etc and the CRT's everything else

 mozcrt.lib: $(IMPORT_LIBRARY) msvc_modified.lib

 	lib -OUT:$@ $^

 # Put the fixed object file back in

 msvc_modified.lib: msvc_removed.lib crtdll_fixed.obj

 	lib -OUT:$@ $^

 # Fix the object file

 crtdll_fixed.obj: crtdll.obj

 	$(PYTHON) $(srcdir)/fixcrt.py

 # Find the path of crtdll.obj

 CRTDLL_FULLPATH=$(subst \,\\,$(shell lib -list msvc_combined.lib | grep crtdll\\.obj))

 # Remove the broken object file, only after we have extracted it

 msvc_removed.lib: msvc_combined.lib crtdll.obj

 	lib -OUT:$@ msvc_combined.lib -REMOVE:$(CRTDLL_FULLPATH)

 # Extract the broken object file out of the combined library

 crtdll.obj: msvc_combined.lib

 	lib -OUT:$@ $^ -EXTRACT:$(CRTDLL_FULLPATH)

 # Grab both CRT libraries and combine them into one library to simplify things

 msvc_combined.lib:

 	lib -OUT:$@ $(WIN32_CRT_LIBS)

 endif

 endif # MOZ_MEMORY