Changes between Version 26 and Version 27 of ubuntu

Timestamp:

04/13/2022 08:02:37 PM (4 years ago)

Author:

Tim Harvey

Comment:

added cross-compile examples

ubuntu

@@ -353 +353 @@
 }}}
 
-
 [=#hello-world.c]
+== Cross compiling example
+If you wish to compile applications on a development host intended to run on a target with a different architecture (ie you have an x86 host, and an arm64 target like Venice or Newport) you can use Ubuntu's cross toolchain which consits of a gcc cross-compiler, libc, and binutils.
+
+Example:
+ * cross compile for ARM64 (Venice / Newport) on X86 Ubuntu host:
+{{{#!bash
+# install Ubuntu cross-build package
+sudo apt update
+sudo apt install crossbuild-essential-arm64 # installs gcc as well as binutils and libs
+aarch64-linux-gnu-gcc -v # see gcc version if interested
+# build a simple app, using shared libraries
+cat << EOF >> helloworld.c
+#include <stdio.h>
+
+int main (int argc, char** argv)
+{
+   printf("Hello World\n");
+   return 0;
+}
+EOF
+aarch64-linux-gnu-gcc helloworld.c -o helloworld
+file helloworld # shows ELF 64-bit LSB shared object, ARM aarch64, dynamically linked with interpreter /lib/ld-linux-aarch64.so.1
+aarch64-linux-gnu-objdump -x helloworld | grep NEEDED # show libs needed on target
+}}}
+  - this was tested on both an Ubuntu bionic dev host (providing gcc-v7.5) as well as an Ubuntu focal dev host (providing gcc-v9.4.0)
+ * cross compile for ARM32 (Ventana) on X86 Ubuntu host:
+{{{#!bash
+# install Ubuntu cross-build package
+sudo apt update
+sudo apt install crossbuild-essential-armel # installs gcc as well as binutils and libs
+arm-linux-gnueabi-gcc -v # see gcc version if interested
+# build a simple app, using shared libraries
+cat << EOF >> helloworld.c
+#include <stdio.h>
+
+int main (int argc, char** argv)
+{
+   printf("Hello World\n");
+   return 0;
+}
+EOF
+arm-linux-gnueabi-gcc helloworld.c -o helloworld
+file helloworld # shows ELF 32-bit LSB ARM EABI5v1 shared object, dynamically linked with interpreter /lib/ld-linux.so.3
+arm-linux-gnueabi-objdump -x helloworld | grep NEEDED # show libs needed on target
+}}}
+
+
+
 == Native compiling example
 While typically not as fast as cross-compiling on a higher end processing Linux development host it can be simple to compile ANSI-C code natively on a Gateworks board running an Ubuntu OS.