Add stage-specific AS variables to the build system

mk/config.mk.in

@@ -548,6 +548,11 @@ CC_STAGE0       = @CC_STAGE0@
 CC_STAGE1       = $(CC)
 CC_STAGE2       = $(CC)
 CC_STAGE3       = $(CC)
+AS              = $(WhatGccIsCalled)
+AS_STAGE0       = @CC_STAGE0@
+AS_STAGE1       = $(AS)
+AS_STAGE2       = $(AS)
+AS_STAGE3       = $(AS)
 
 # C compiler and linker flags from configure (e.g. -m<blah> to select
 # correct C compiler backend). The stage number is the stage of GHC

rules/c-suffix-rules.mk

@@ -49,7 +49,7 @@ $1/$2/build/%.$$($3_osuf) : $1/$2/build/%.c
 	"$$($1_$2_CC)" $$($1_$2_$3_ALL_CC_OPTS) -c $$< -o $$@
 
 $1/$2/build/%.$$($3_osuf) : $1/$2/build/%.$$($3_way_)s
-	"$$(AS)" $$($1_$2_$3_ALL_AS_OPTS) -o $$@ $$<
+	"$$($1_$2_AS)" $$($1_$2_$3_ALL_AS_OPTS) -o $$@ $$<
 
 $1/$2/build/%.$$($3_osuf) : $1/%.S | $$$$(dir $$$$@)/.
 	"$$($1_$2_CC)" $$($1_$2_$3_ALL_CC_OPTS) -c $$< -o $$@

rules/package-config.mk

@@ -17,6 +17,7 @@ $(call profStart, package-config($1,$2,$3))
 
 $1_$2_HC = $$(GHC_STAGE$3)
 $1_$2_CC = $$(CC_STAGE$3)
+$1_$2_AS = $$(AS_STAGE$3)
 $1_$2_AR = $$(AR_STAGE$3)
 $1_$2_AR_OPTS = $$(AR_OPTS_STAGE$3)
 $1_$2_EXTRA_AR_ARGS = $$(EXTRA_AR_ARGS_STAGE$3)