atari: autodetect ATARIARCH

Can still be set explicitly if needed, but the defaults are now
sane.

Author: jmb202

frontends/atari/Makefile

@@ -12,6 +12,19 @@ STRIP := $(wildcard $(GCCSDK_INSTALL_CROSSBIN)/*-strip)
 STACK := $(wildcard $(GCCSDK_INSTALL_CROSSBIN)/*stack)
 FT2CF := $(GCCSDK_INSTALL_ENV)/bin/freetype-config
 
+# Compute default atariarch: 68020-60 unless coldfire
+ifeq ($(origin ATARIARCH),undefined)
+  ifeq (,$(findstring m5475,$(shell $(CC) -dumpmachine 2>/dev/null)))
+    ATARIARCH := 68020-60
+  else
+    ATARIARCH := v4e
+  endif
+endif
+# Validate atariarch
+ifeq ($(filter 68000 68020-60 v4e,$(ATARIARCH)),)
+  $(error Unknown ATARIARCH "$(ATARIARCH)")
+endif
+
 ifeq ($(ATARIARCH),68000)
 PRGSUFFIX := 000.app
 PKGNAME := ns000.zip

frontends/atari/Makefile.defaults

@@ -39,10 +39,6 @@ NETSURF_USE_ATARI_VDI_FONT := NO
 # Valid options: YES, NO
 NETSURF_USE_ATARI_8BPP_SUPPORT := NO
 
-# Configure the CPU target
-# Valid options: 68000, 68020-60, 5475 (coldfire)
-ATARIARCH = 68020-60
-
 # enable optimizations
 # -O2 is currently broken with m68000 / m68020-60 builds
 CFLAGS += -O3