docs: Cross compilation

docs/development/build-instructions-linux.md

@@ -23,13 +23,11 @@ $ sudo apt-get install build-essential clang libdbus-1-dev libgtk2.0-dev \
 Other distributions may offer similar packages for installation via package
 managers such as yum. Or one can compile from source code.
 
-
 ## If You Use Virtual Machines For Building
 
 If you plan to build electron on a virtual machine, you will need a fixed-size
 device container of at least 25 gigabytes in size.
 
-
 ## Getting the code
 
 ```bash
@@ -48,6 +46,15 @@ $ cd electron
 $ ./script/bootstrap.py -v
 ```
 
+### Cross compilation
+
+If you want to cross compile for `arm` or `ia32` targets, you can pass the
+`--target_arch` parameter to the `bootstrap.py` script:
+
+```bash
+$ ./script/bootstrap.py -v --target_arch=arm
+```
+
 ## Building
 
 If you would like to build both `Release` and `Debug` targets:
@@ -75,20 +82,16 @@ You can also build the `Debug` target only:
 $ ./script/build.py -c D
 ```
 
-After building is done, you can find the `electron` debug binary 
-under `out/D`.
-
+After building is done, you can find the `electron` debug binary under `out/D`.
 
 ## Cleaning
 
-
 To clean the build files:
 
 ```bash
 $ ./script/clean.py
 ```
 
-
 ## Troubleshooting
 
 Make sure you have installed all the build dependencies.