Usable compiler executable

After installing a MinGW-w64 based toolchain, one often explores their installation directory (prefix for this answer) and discovers multiple versions of the same build tool living in different locations. Which version should be used?

Short Answer

Always use the executables found in the immediate bin subdirectory of the installation directory, i.e. the executables living in <prefix>/bin.

Long Answer

Depending upon your system and how the MinGW-w64 toolchain was built, you'll discover build tools living in <prefix>/bin and <prefix>/<target-alias>/bin. For example, on a Windows 64bit machine using one of the pre-built 64bit toolchains, executables live in <prefix>/bin and <prefix>/x86_64-w64-mingw32/bin. Use only the executables in <prefix>/bin. The executables in <prefix>/bin are meant to be directly invoked by developers building software with the toolchain. The executables living in <prefix>/<target-alias>/bin are used internally by the build tools and must never be directly invoked.

Repeat after me: I will never directly invoke the executables living in <prefix>/<target-alias>/bin.

A related issue is build tool naming. Depending upon how your toolchain was built, you may find both prefixed and non-prefixed versions of tools in <prefix>/bin for the gcc compiler driver and other tools. For example, on my Windows 64bit machine with a pre-built 64bit toolchain, both gcc.exe and x86_64-w64-mingw32-gcc.exe exist in <prefix>/bin. Which one should be invoked? While it is perfectly acceptable to directly invoke x86_64-w64-mingw32-gcc.exe, unless you are cross compiling (the reason why build tool executables use the prefixed name convention) it is often more convenient to invoke the non-prefixed gcc.exe. The same advice goes for other executables living in <prefix>/bin.

If your particular toolchain provides only prefixed executables in <prefix>/bin, it is acceptable to directly invoke those executables. Often, those who find the prefixed executable names living in <prefix>/bin too verbose simply create more conveniently named symlinks or renamed copies of the original executable.