Start updating XDK1 rules

Makefile

@@ -72,6 +72,15 @@ PLAT=_unix
 endif
 endif
 
+SPACE :=
+SPACE := $(SPACE) $(SPACE)
+BACKSLASH :=
+BACKSLASH := \$(BACKSLASH)
+filter_out1 = $(filter-out $(firstword $1),$1)
+filter_out2 = $(call filter_out1,$(call filter_out1,$1))
+unixpath = $(subst \,/,$1)
+unixcygpath = /$(subst :,,$(call unixpath,$1))
+
 # UNIX
 ifeq ($(platform), unix)
 	EXT    ?= so
@@ -300,13 +309,13 @@ else ifeq ($(platform), emscripten)
 # Windows MSVC 2003 Xbox 1
 else ifeq ($(platform), xbox1_msvc2003)
 TARGET := $(TARGET_NAME)_libretro_xdk1.lib
-MSVCBINDIRPREFIX = $(XDK)/xbox/bin/vc71
-CC  = "$(MSVCBINDIRPREFIX)/CL.exe"
-CXX  = "$(MSVCBINDIRPREFIX)/CL.exe"
-LD   = "$(MSVCBINDIRPREFIX)/lib.exe"
+CC  = CL.exe
+CXX  = CL.exe
+LD   = lib.exe
 
 export INCLUDE := $(XDK)/xbox/include
 export LIB := $(XDK)/xbox/lib
+PATH := $(call unixcygpath,$(XDK)/xbox/bin/vc71):$(PATH)
 PSS_STYLE :=2
 CFLAGS   += -D_XBOX -D_XBOX1
 CXXFLAGS += -D_XBOX -D_XBOX1

Makefile.common

+LIBRETRO_COMM_DIR  = $(CORE_DIR)/libretro-common
 LIBFLAC_DIR    = $(CORE_DIR)/deps/libFLAC
 LIBVORBIS_DIR  = $(CORE_DIR)/deps/libvorbis
 LIBOGG_DIR     = $(CORE_DIR)/deps/libogg
 
 INCFLAGS   := \
 	-I$(CORE_DIR) \
-	-I$(CORE_DIR)/libretro-common/include \
+	-I$(LIBRETRO_COMM_DIR)/include \
 	-I$(CORE_DIR)/include \
 
+ifneq (,$(findstring msvc2003,$(platform)))
+INCFLAGS += -I$(LIBRETRO_COMM_DIR)/include/compat/msvc
+endif
+
 SOURCES_C :=  \
 	$(CORE_DIR)/common/cl_input.c \
 	$(CORE_DIR)/common/cd_common.c \