It's not generally needed. It was added in
https://github.com/tinygo-org/tinygo/pull/3958 to fix an issue with
binaryen that has since been fixed in a different way, so we don't need
the googletest dependency anymore.
Without this change, my tinygo builds crash with
SIGSEGV: segmentation violation
PC=0x10884f87c m=16 sigcode=2
signal arrived during cgo execution
goroutine 378 [syscall]:
runtime.cgocall(0x100631e44, 0x1401755be88)
/nix/store/4hf287252ilsdf2w36mfm8fa0rvbf33w-go-1.21.4/share/go/src/runtime/cgocall.go:157 +0x44 fp=0x1401755be50 sp=0x1401755be10 pc=0x1002a5084
tinygo.org/x/go-llvm._Cfunc_LLVMGoWriteThinLTOBitcodeToMemoryBuffer(0x123614160)
_cgo_gotypes.go:6078 +0x34 fp=0x1401755be80 sp=0x1401755be50 pc=0x1004b66b4
...
and reports using LLVM 16:
$ tinygo version
tinygo version 0.31.0-dev darwin/arm64 (using go version go1.21.4 and LLVM version 16.0.6)
I don't know why libcxx-16 is being included, but explicitly specifying
llvmPackages_17.libcxx fixes the crash and version skew.
The default on MacOS is `md5`, while Nix only has `md5sum` available.
Therefore, make it possible to override the variable via the environment
so that flake.nix can set the correct binary name.
This adds a flake.nix file that makes it possible to quickly create a
development environment.
You can download Nix here, for use on your Linux or macOS system:
https://nixos.org/download.html
After you have installed Nix, you can enter the development environment
as follows:
nix develop
This drops you into a bash shell, where you can install TinyGo simply
using the following command:
go install
That's all! Assuming you've set up your $PATH correctly, you can now use
the tinygo command as usual:
tinygo version
You can also do many other things from this environment. Building and
flashing should work as you're used to: it's not a VM or container so
there are no access restrictions.
Ayke van Laethem
Elias Naur
Flavio Castelli