build: make python executable configurable

Makefile

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 12 matching lines @@
 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 
 # Variable default definitions. Override them by exporting them in your shell.
 CXX ?= g++
 LINK ?= g++
 OUTDIR ?= out
+PYTHON ?= python
 TESTJOBS ?=
 GYPFLAGS ?=
 TESTFLAGS ?=
 ANDROID_NDK_ROOT ?=
 ANDROID_TOOLCHAIN ?=
 ANDROID_V8 ?= /data/local/v8
 
 # Special build flags. Use them like this: "make library=shared"
 
 # library=shared || component=shared_library
@@ skipping 66 matching lines @@
 endif
 # regexp=interpreted
 ifeq ($(regexp), interpreted)
   GYPFLAGS += -Dv8_interpreted_regexp=1
 endif
 # hardfp=on
 ifeq ($(hardfp), on)
   GYPFLAGS += -Dv8_use_arm_eabi_hardfloat=true
 endif
 
+GYPFLAGS += "-Dpython=$(PYTHON)"
+
 # ----------------- available targets: --------------------
 # - "dependencies": pulls in external dependencies (currently: GYP)
 # - any arch listed in ARCHES (see below)
 # - any mode listed in MODES
 # - every combination <arch>.<mode>, e.g. "ia32.release"
 # - "native": current host's architecture, release mode
 # - any of the above with .check appended, e.g. "ia32.release.check"
 # - "android": cross-compile for Android/ARM
 # - default (no target specified): build all DEFAULT_ARCHES and MODES
 # - "check": build all targets and run all tests
@@ skipping 47 matching lines @@
 .SECONDEXPANSION:
 $(MODES): $(addsuffix .$$@,$(DEFAULT_ARCHES))
 
 $(ARCHES): $(addprefix $$@.,$(MODES))
 
 # Defines how to build a particular target (e.g. ia32.release).
 $(BUILDS): $(OUTDIR)/Makefile.$$(basename $$@)
         @$(MAKE) -C "$(OUTDIR)" -f Makefile.$(basename $@) \
                  CXX="$(CXX)" LINK="$(LINK)" \
                  BUILDTYPE=$(shell echo $(subst .,,$(suffix $@)) | \
-                             python -c "print raw_input().capitalize()") \
+                             $(PYTHON) -c "print raw_input().capitalize()") \
                  builddir="$(shell pwd)/$(OUTDIR)/$@"
 
 native: $(OUTDIR)/Makefile.native
         @$(MAKE) -C "$(OUTDIR)" -f Makefile.native \
                  CXX="$(CXX)" LINK="$(LINK)" BUILDTYPE=Release \
                  builddir="$(shell pwd)/$(OUTDIR)/$@"
 
 $(ANDROID_ARCHES): $(addprefix $$@.,$(MODES))
 
 $(ANDROID_BUILDS): $(GYPFILES) $(ENVFILE) build/android.gypi \
@@ skipping 50 matching lines @@
         rm -f $(OUTDIR)/Makefile.native
         rm -rf $(OUTDIR)/native
         find $(OUTDIR) -regex '.*\(host\|target\).native\.mk' -delete
 
 clean: $(addsuffix .clean, $(ARCHES) $(ANDROID_ARCHES)) native.clean
 
 # GYP file generation targets.
 OUT_MAKEFILES = $(addprefix $(OUTDIR)/Makefile.,$(ARCHES))
 $(OUT_MAKEFILES): $(GYPFILES) $(ENVFILE)
         GYP_GENERATORS=make \
-        build/gyp/gyp --generator-output="$(OUTDIR)" build/all.gyp \
+        $(PYTHON) build/gyp/gyp --generator-output="$(OUTDIR)" build/all.gyp \
                       -Ibuild/standalone.gypi --depth=. \
                       -Dv8_target_arch=$(subst .,,$(suffix $@)) \
                       -S.$(subst .,,$(suffix $@)) $(GYPFLAGS)
 
 $(OUTDIR)/Makefile.native: $(GYPFILES) $(ENVFILE)
         GYP_GENERATORS=make \
-        build/gyp/gyp --generator-output="$(OUTDIR)" build/all.gyp \
+        $(PYTHON) build/gyp/gyp --generator-output="$(OUTDIR)" build/all.gyp \
                       -Ibuild/standalone.gypi --depth=. -S.native $(GYPFLAGS)
 
 must-set-ANDROID_NDK_ROOT_OR_TOOLCHAIN:
 ifndef ANDROID_NDK_ROOT
 ifndef ANDROID_TOOLCHAIN
           $(error ANDROID_NDK_ROOT or ANDROID_TOOLCHAIN must be set))
 endif
 endif
 
 # Replaces the old with the new environment file if they're different, which
 # will trigger GYP to regenerate Makefiles.
 $(ENVFILE): $(ENVFILE).new
         @if test -r $(ENVFILE) && cmp $(ENVFILE).new $(ENVFILE) >/dev/null; \
             then rm $(ENVFILE).new; \
             else mv $(ENVFILE).new $(ENVFILE); fi
 
 # Stores current GYPFLAGS in a file.
 $(ENVFILE).new:
         @mkdir -p $(OUTDIR); echo "GYPFLAGS=$(GYPFLAGS)" > $(ENVFILE).new; \
             echo "CXX=$(CXX)" >> $(ENVFILE).new
 
 # Dependencies.
 # Remember to keep these in sync with the DEPS file.
 dependencies:
         svn checkout --force http://gyp.googlecode.com/svn/trunk build/gyp \
             --revision 1501