gawk.exe builds for Windows

GNU awk 3.1.8 is only distributed as source from ftp.gnu.org/gnu/gawk, and the old GnuWin32 binary builds are unmaintained. This repository builds a native Windows gawk.exe from the unmodified GNU tarball with GitHub Actions and publishes it as a release here.

The build uses the MinGW-w64 toolchain (via MSYS2) and the DOS/Windows port that ships inside the tarball's pc/ directory (make mingw32), the same approach the historical GnuWin32 packages used. The result is a standalone native win32 executable that links against Microsoft's C runtime (msvcrt.dll, msvcp60.dll) — no Cygwin or MSYS emulation layer.

The one modern patch needed is shim/langinfo.h: MinGW has no <langinfo.h>, which the GnuWin32 builds got from LibGw32C. The shim provides the single nl_langinfo(CODESET) call gawk makes.

Cutting a release

1. Put the gawk version into GAWK_VERSION, e.g. 3.1.8.

2. Commit, tag the commit, and push both:

   git commit -am "gawk 3.1.8"
   git tag v3.1.8
   git push origin HEAD v3.1.8

The build workflow then downloads gawk-<version>.tar.gz from ftp.gnu.org, builds it with make mingw32, smoke-tests the result (runs it and verifies it depends only on Windows system DLLs), and creates a release for the pushed tag with these assets:

• gawk.exe — GNU awk (x86-64, stripped)
• pgawk.exe — profiling GNU awk
• COPYING — license (GPL), from the source tarball
• sha256sums.txt

The workflow fails if the pushed tag does not match the contents of GAWK_VERSION, so a stale file can't produce a mislabeled release.

Building without a tag

Run the workflow manually (Actions → build → Run workflow) and enter the version, or:

gh workflow run build -f gawk_version=3.1.8

Note: the pc/-port build recipe is verified for gawk 3.1.8. Other 3.1.x versions will likely build the same way; 4.x+ changed its Windows build and may need workflow changes.