[mac] Fix cross-compilation for Android from a Mac

docs/building_with_gyp.md

 **Build issues? File a bug at code.google.com/p/v8/issues or ask for help on v8-users@googlegroups.com.**
 
 # Building V8
 
 V8 is built with the help of [GYP](http://code.google.com/p/gyp/). GYP is a meta build system of sorts, as it generates build files for a number of other build systems. How you build therefore depends on what "back-end" build system and compiler you're using.
 The instructions below assume that you already have a [checkout of V8](using_git.md) but haven't yet installed the build dependencies.
 
 If you intend to develop on V8, i.e., send patches and work with changelists, you will need to install the dependencies as described [here](using_git.md).
 
 
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 xcodebuild -project build/all.xcodeproj -configuration Release
 xcodebuild -project build/all.xcodeproj
 ```
 
 Note: If you have configured your `GYP_GENERATORS` environment variable, either unset it, or set it to `xcode` for this to work.
 
 
 #### Custom build settings
 
 You can export the `GYP_DEFINES` environment variable in your shell to configure custom build options. The syntax is `GYP_DEFINES="-Dvariable1=value1 -Dvariable2=value2"` and so on for as many variables as you wish. Possibly interesting options include:
+
   * `-Dcomponent=shared_library` (see `library=shared` in the [GCC + make](#Optional_parameters.md) section above)
   * `-Dconsole=readline` (see `console=readline`)
   * `-Dv8_enable_disassembler=1` (see `disassembler=on`)
   * `-Dv8_use_snapshot='false'` (see `snapshot=off`)
   * `-Dv8_enable_gdbjit=1` (see `gdbjit=on`)
   * `-Dv8_use_liveobjectlist=true` (see `liveobjectlist=on`)
 
 
 ### Visual Studio
 
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 ```
 
 
 ### MinGW
 
 Building on MinGW is not officially supported, but it is possible. You even have two options:
 
 #### Option 1: With Cygwin Installed
 
 Requirements:
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   * MinGW
   * Cygwin, including Python
   * Python from www.python.org _(yes, you need two Python installations!)_
 
 Building:
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   1. Open a MinGW shell
   1. `export PATH=$PATH:/c/cygwin/bin` _(or wherever you installed Cygwin)_
   1. `make ia32.release -j8`
 
 Running tests:
+
   1. Open a MinGW shell
   1. `export PATH=/c/Python27:$PATH` _(or wherever you installed Python)_
   1. `make ia32.release.check -j8`
 
 #### Option 2: Without Cygwin, just MinGW
 
 Requirements:
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   * MinGW
   * Python from www.python.org
 
 Building and testing:
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   1. Open a MinGW shell
   1. `tools/mingw-generate-makefiles.sh` _(re-run this any time a `*`.gyp`*` file changed, such as after updating your checkout)_
   1. `make ia32.release` _(unfortunately -jX doesn't seem to work here)_
   1. `make ia32.release.check -j8`
 
 
 # Final Note
 <font color='darkred'><b>If you have problems or questions, please file bugs at code.google.com/p/v8/issues or send mail to v8-users@googlegroups.com. Comments on this page are likely to go unnoticed and unanswered.</b></font>