The MSVC build system already did this, and commit
617dc6d299c957e2784320382b3277ede01d9c63 used it in a second file.
Back-patch to 9.4, like that commit.
Discussion: https://postgr.es/m/CAA8=A7_1SWc3+3Z=-utQrQFOtrj_DeohRVt7diA2tZozxsyUOQ@mail.gmail.com
OBJS= dest.o fastpath.o postgres.o pquery.o utility.o
-ifneq (,$(filter $(PORTNAME),cygwin win32))
-override CPPFLAGS += -DWIN32_STACK_RLIMIT=$(WIN32_STACK_RLIMIT)
-endif
-
include $(top_srcdir)/src/backend/common.mk
DLSUFFIX = .dll
CFLAGS_SL =
+override CPPFLAGS += -DWIN32_STACK_RLIMIT=$(WIN32_STACK_RLIMIT)
+
ifneq (,$(findstring backend,$(subdir)))
ifeq (,$(findstring conversion_procs,$(subdir)))
ifeq (,$(findstring libpqwalreceiver,$(subdir)))
override CPPFLAGS+="-I$(top_srcdir)/src/include/port/win32"
endif
+override CPPFLAGS += -DWIN32_STACK_RLIMIT=$(WIN32_STACK_RLIMIT)
+
AROPT = crs
DLSUFFIX = .dll
CFLAGS_SL =