This should not happen under normal circumstances. It can still happen
when there is a mismatch between TinyGo version and the associated
runtime, or while developing the compiler package.
When a function is exported using //export, but also had a
//go:wasm-module pragma, the //export name was ignored. The
//go:wasm-module doesn't actually do anything besides breaking the
export (exported functions don't have a module name).
I've refactored and cleaned up the code, and in the process removed this
weird edge case.
This replaces our own manual detection of various variables (GOROOT,
GOPATH, Go version) with a simple call to `go env`.
If the `go` command is not found:
error: could not find 'go' command: executable file not found in $PATH
If the Go version is too old:
error: requires go version 1.18 through 1.20, got go1.17
If the Go tool itself outputs an error (using GOROOT=foobar here):
go: cannot find GOROOT directory: foobar
This does break the case where `go` wasn't available in $PATH but we
would detect it anyway (via some hardcoded OS-dependent paths). I'm not
sure we want to fix that: I think it's better to tell users "make sure
`go version` prints the right value" than to do some automagic detection
of Go binary locations.
This is a small change that's not really important in itself, but it
avoids duplicate errors in a future commit that adds error messages to
//go:wasmimport.
These functions can be implemented more efficiently using LLVM
intrinsics. That makes them the Go equivalent of functions like
__builtin_clz which are also implemented using these LLVM intrinsics.
I believe the Go compiler does something very similar: IIRC it converts
calls to these functions into optimal instructions for the given
architecture.
I tested these by running `tinygo test math/bits` after uncommenting the
tests that would always fail (the *PanicZero and *PanicOverflow tests).
This gives a small improvement now, and is needed to be able to use the
Heap2Stack transform that's available in the Attributor pass. This
Heap2Stack transform could replace our custom OptimizeAllocs pass.
Most of the changes are just IR that changed, the actual change is
relatively small.
To give an example of why this is useful, here is the code size before
this change:
$ tinygo build -o test -size=short ./testdata/stdlib.go
code data bss | flash ram
95620 1812 968 | 97432 2780
$ tinygo build -o test -size=short ./testdata/stdlib.go
code data bss | flash ram
95380 1812 968 | 97192 2780
That's a 0.25% reduction. Not a whole lot, but nice for such a small
patch.
It is possible to create function-local named types:
func foo() any {
type named int
return named(0)
}
This patch makes sure they don't alias with named types declared at the
package scope.
Bug originally found by Damian Gryski while working on reflect support.
Previously we only supported recursive types in structs. But there can
be other kinds of recursive types, like slices:
type RecursiveSlice []RecursiveSlice
This doesn't involve structs, so it led to infinite recursion in the
compiler. This fix avoids recursion at the proper level: at the place
where the named type is defined.
Previously we were using a really weird calculation to determine the
alignment in bits - written by me (no idea what I was thinking at the
time, it's obviously incorrect). Just replace it with the much more
obviously correct multiplication by 8 to get bits from bytes.
Found while working on properly dealing with alignment in `-size=full`.
There was a mostly benign race condition in the compiler. The issue was
that there is a check for type aliases (which can alias types in another
function), but this check was _after_ accessing a property of the
function that might not have been completed.
I don't think this can have any serious effects, as the function is
skipped anyway, but such bugs should certainly be fixed.
If there is no source location, at least use the file (but not line) for
debug information.
This attributes almost 1kB of string data for ./testdata/stdlib.go when
compiling for WASI.
This is helpful for WebAssembly: it makes it possible to attribute many
more data to locations in the source code, which makes `-size=full` more
useful.
