This is only very minimal support. More support (such as tinygo flash,
or peripheral access) should be added in later commits, to keep this one
focused.
Importantly, this commit changes the LLVM repo from llvm/llvm-project to
tinygo-org/llvm-project. This provides a little bit of versioning in
case something changes in the Espressif fork. If we want to upgrade to
LLVM 11 it's easy to switch back to llvm/llvm-project until Espressif
has updated their fork.
It appears that version 2020.07.22 or 2020.07.23 introduced a breaking
change in RISC-V. We will have to fix this eventually, but for now it's
easiest to just pin the QEMU version. Once this new QEMU version
(version 5?) is more widely available, it becomes easier to debug and
fix the underlying cause.
This commit also adds a bit of version independence, in particular for
external commands. It also adds the LLVM version to the `tinygo version`
command, which might help while debugging.
This makes the `make wasi-libc` command much more reliable and makes the
CI configuration simpler. Also, it avoids warnings when they are not
relevant.
The wasi-libc Makefile uses the `find` command line tool. Unfortunately,
it was using the Windows find version instead of the MinGW version,
leading to lots of errors at a later stage.
This commit prepends /usr/bin to `$PATH` to make sure the MinGW version
is found first.
This allows CGo code to call some libc functions. Additionally, by
putting memset/memmove/memcpy in an archive they're not included anymore
when not necessary, reducing code size for small programs.
Zip files are far more often used on Windows systems, so we provide zip
files in releases. Unfortunately, previously the provided artifact in CI
was really just a compressed .tar.gz file, which defeats the purpose.
This commit zips the release tarball itself so it can be downloaded as
an artifact.
Now that we use LLVM 9, RISC-V support in LLVM has far fewer bugs and we
can avoid the GNU toolchain.
* replace GNU linker with lld
* replace GCC with clang
Additionally, RISC-V was promoted to stable so it can be enabled by
default in CI.
The default Go version is 1.12. Because Go 1.13 introduced language
changes (improved numeric constants), TinyGo compiled with Go 1.12
cannot handle Go 1.13 code such as the Go 1.13 standard library.
Use Go 1.13 to build TinyGo on Azure Pipelines to fix this.