Cross Compilation

[singhPrabhat]

Hi Everyone,

I want to make executable for 32-bit machine by using Makefile on 64-bit machine.
Currently I am having gcc4.2.1 on my box.


Thanks.

[arnaudk]

Look at reference for gcc compiler flags, paying particular attention to the section "Target Options".

[singhPrabhat]

Look at reference for gcc compiler flags, paying particular attention to the section "Target Options".

-b machine how can I find the value for machine?

how can I configure cross compiler? As in the link given by you tell about
For example, if a cross-compiler was configured with `configure arm-elf', meaning to compile for an arm processor with elf binaries, then you would specify -b arm-elf to run that cross compiler

I want to make executable for 32-bit machine.

can you guide me on how to write gcc command in Makefile for cross compilation.

Thanks for your response.

[arnaudk]

You'll need to install a version of gcc for each target machine type to use it as a cross compiler, see installation instructions. There are some exceptions. For example, if your gcc is installed on a 64-bit intel machine, and you simply want to compile for a 32-bit intel machine, then you can use intel hardware options such as -m32. The same applies to other hardware platforms. Have a good look through the manual and use google.

[singhPrabhat]

You'll need to install a version of gcc for each target machine type to use it as a cross compiler, see installation instructions. There are some exceptions. For example, if your gcc is installed on a 64-bit intel machine, and you simply want to compile for a 32-bit intel machine, then you can use intel hardware options such as -m32. The same applies to other hardware platforms. Have a good look through the manual and use google.

my target machine is having gcc3.2.2 and my local machine is gcc4.2.1. Do I need to install gcc3.2.2 on my local box?

how can I find option (-b) for the target machine?

CCWebBrowser: $(OBJs)

$(GCC) -m32 -o CCWebBrowser.linux $(OBJs) $(LSSLLIBs) $(LICULIBs)

If I give target as above then it creates executable but for 64-bit.

[arnaudk]

The compiler version on your target machine doesn't matter because you're not going to use it when you run the program there.

You need to specify -m32 for the dependencies as well. You can do this easily by changing the line which looks something like GCC = g++ into something like GCC = g++ -m32. Make sure you do a full rebuild. Note also that you'll need to link in 32bit versions of any libraries you use as well...

I think it may be easier just to configure a version of gcc tailored to targeted platform as per the installation instructions. Then to compile your code for your target machine change the line to GCC = <target-platform>-g++