Getting Started Guide Building user programs The GNU tools

The GNU tools

The GNU tools used to build user programs from C or C++ source code traditionally have names such as:

gcc

for the GNU C compiler,

g++

for the GNU C++ compiler,

cpp

for the GNU C pre-processor,

ld

for the GNU linker,

as

for the GNU assembler,

ar

for the GNU librarian.

On the Linux host system x86 PC, these executable names are already in use by the native x86 Linux GNU tools. To differentiate the names, the STLinux cross tools have a filename prefix of:

sh4-linux-

for the ST40 Linux cross tools,

st231-linux-

for the ST231 Linux cross tools.

For example, the cross version of gcc for the ST231 Linux system is called st231-linux-gcc and the for the ST40 Linux system it is called sh4-linux-gcc.

On the Linux target system, the tools can have their default names (for example, gcc), but for convenience when moving build scripts between the cross and the native environments, the cross names (for example, sh4-linux-gcc) are also provided. The executables referenced by these two names are identical.

When working in cross development mode, the tools produce their output in the file system of the host machine. However, these executables are not x86 executables for the host machine, but are SoC executables for the target. Therefore they need to be made visible to the target Linux system so they can be loaded and executed. The easiest way to do this during development, is to place them within the part of the host PC file system which has been NFS mounted by the target system. In this way, they are accessible from both the cross development host Linux system and the target Linux environment, and can be run from the shell of the target like any other user program.

When working in native target development mode, the tools operate in the familiar way; the target system is used directly as the development host.