allow building julia without extra precompile statements (JuliaLang#2…

…9132)

Make.inc

@@ -10,6 +10,10 @@
 ## variable declarations. The spaces between the variable value and the
 ## comment will be included in the value.
 
+# Julia precompilation options
+# Set to zero to turn off extra precompile (e.g. for the REPL)
+JULIA_PRECOMPILE ?= 1
+
 # OPENBLAS build options
 OPENBLAS_TARGET_ARCH:=
 OPENBLAS_SYMBOLSUFFIX:=

Makefile

@@ -206,7 +206,7 @@ define sysimg_builder
 $$(build_private_libdir)/sys$1-o.a $$(build_private_libdir)/sys$1-bc.a : $$(build_private_libdir)/sys$1-%.a : $$(build_private_libdir)/sys.ji
 	@$$(call PRINT_JULIA, cd $$(JULIAHOME)/base && \
 	if ! $$(call spawn,$3) $2 -C "$$(JULIA_CPU_TARGET)" --output-$$* $$(call cygpath_w,$$@).tmp $$(JULIA_SYSIMG_BUILD_FLAGS) \
-		--startup-file=no --warn-overwrite=yes --sysimage $$(call cygpath_w,$$<) $$(call cygpath_w,$$(JULIAHOME)/contrib/generate_precompile.jl); then \
+		--startup-file=no --warn-overwrite=yes --sysimage $$(call cygpath_w,$$<) $$(call cygpath_w,$$(JULIAHOME)/contrib/generate_precompile.jl) $(JULIA_PRECOMPILE); then \
 		echo '*** This error is usually fixed by running `make clean`. If the error persists$$(COMMA) try `make cleanall`. ***'; \
 		false; \
 	fi )

contrib/generate_precompile.jl

@@ -1,5 +1,9 @@
 # This file is a part of Julia. License is MIT: https://julialang.org/license
 
+if !isempty(ARGS)
+    ARGS[1] == "0" && exit(0)
+end
+
 # Prevent this from being put into the Main namespace
 let
 M = Module()