WorkingWithGnatGPL

C library

These RTSs need a C library. The GNAT GPL cross-compiler as supplied by AdaCore for Linux and Windows doesn't include a C library, so you'll need to build your own and install it. These instructions are for Linux; for Windows, at least the --prefix setting will need to change to match your compiler.

Obtain Newlib, unpack it into newlib-2.2.0 (or later version, of course). You'll need to build in a parallel directory (in other words, don't configure in the source directory!). Assuming your GNAT GPL 2016 compiler is installed at /opt/gnat-gpl-2016,

mkdir newlib-2.2.0-build
cd newlib-2.2.0-build
../newlib-2.2.0/configure \
  --build=x86_64-pc-linux-gnu \
  --target=arm-eabi \
  --prefix=/opt/gnat-gpl-2016 \
  --with-arch=armv7 \
  --with-mode-thumb \
  --enable-multilib \
  --with-gnu-as \
  --with-gnu-ld \
  --disable-nls \
  --disable-newlib-supplied-syscalls

and then make and install:

$ make
$ sudo make install