Summary

When I iteratively create an instance of a module and then close it, I get an UnableToCreateMemory error.

Additional details

Here is the code I'm running:

package main

import (
	"fmt"
	wasm "github.com/wasmerio/go-ext-wasm/wasmer"
)

func main() {
	bytes, err := wasm.ReadBytes("./simple.wasm")
	if err != nil { panic(err) }

	module, err := wasm.Compile(bytes)
	if err != nil { panic(err) }
	defer module.Close()

	for i:=0; i<1000000; i++ {
		fmt.Println(i)

		instance, err := module.Instantiate()
		if err != nil { panic(err) }
		instance.Close()
	}
}

For reference, here is the body of the simple.wasm file in base64 encoding, but I'd assume the results will be similar with any wasm binary.

AGFzbQEAAAABBwFgAn9/AX8DAgEABAUBcAEBAQUDAQAQBhECfwBBgIDAAAt/AEGAgMAACwdHBQZtZW1vcnkCABlfX2luZGlyZWN0X2Z1bmN0aW9uX3RhYmxlAQALX19oZWFwX2Jhc2UDAApfX2RhdGFfZW5kAwEDc3VtAAAJAQAKCQEHACAAIAFqCw==

Here is the tail of the output that I get:

32723
32724
32725
32726
panic: Failed to instantiate the module:
    link error: unable to create memory: UnableToCreateMemory

goroutine 1 [running]:
main.main()
	/demo/src/hello/hello.go:20 +0x250
exit status 2

The iteration count at which it fails (the last printed number) is non-deterministic, it varies a bit between re-runs.

I must be doing something wrong, can you help find the issue?

This package aims at containing a collection of host functions for multiple hosts, to support WebAssembly modules compiled by the TinyGo and the Go compilers.

For the moment, only the Go host is supported, i.e. it's Go host functions implementations. Host functions have empty implementation.

In the future, it will contain real implementations, and it will be extended to a Rust, Python, PHP, Ruby implementations.

I wonder though if we should support host functions required by the Go compiler. It's really focused on JavaScript, plus it is experimental. cc @MarkMcCaskey @syrusakbary

Summary

I tried doing go get github.com/wasmerio/go-ext-wasm/wasmer

but it throws me error:

../go/src/github.com/wasmerio/go-ext-wasm/wasmer/bridge.go:162:87: cannot use (*_Ctype_struct___13)(instanceContext) (type *_Ctype_struct___13) as type *_Ctype_struct___16 in argument to _Cfunc_wasmer_instance_context_data_get

Additional details

My go env

GOARCH="amd64"
GOBIN=""
GOCACHE="/home/ubuntu/.cache/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/ubuntu/go"
GOPROXY=""
GORACE=""
GOROOT="/usr/local/go"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build913563706=/tmp/go-build -gno-record-gcc-switches"

Initially, I was getting error:

ubuntu@ip:~/1$ go get github.com/wasmerio/go-ext-wasm/wasmer
# github.com/wasmerio/go-ext-wasm/wasmer
exec: "gcc": executable file not found in $PATH

Than I did sudo apt install gcc and installed gcc.

Post that the go get for wasmer is giving mentioned error.

Any pointer on what might have gone wrong?

Describe the bug

I have a wasm module that imports a function ext_print_num that takes an int64 parameter. However when I try to implement it, I get an error saying "conflicting types for ext_print_num".

Maybe this is an issue with int64? My other import functions that accept int32 all work perfectly.

Steps to reproduce

package main

// extern void ext_print_num(void *context, int64_t data);
import "C"

//export ext_print_num
func ext_print_num(context unsafe.Pointer, data int64) {
	return
}

func main() {
	bytes, err := wasm.ReadBytes("mymodule.wasm")
	if err != nil {
		return nil, err
	}
	
	imports, err := wasm.NewImports().Append("ext_print_num", ext_print_num, C.ext_print_num)
	if err != nil {
		return nil, err
	}

	instance, err := wasm.NewInstanceWithImports(bytes, imports)
	if err != nil {
		return nil, err
	}
	defer instance.Close()
}

the full code is here: https://github.com/ChainSafe/gossamer/blob/elizabeth/wasmer/runtime/wasmer.go

Expected behavior

I wouldn't expect an error since the types should match.

Actual behavior

In file included from _cgo_export.c:4:0:
cgo-gcc-export-header-prolog:58:13: error: conflicting types for ‘ext_print_num’
In file included from _cgo_export.c:4:0:
wasmer.go:9:14: note: previous declaration of ‘ext_print_num’ was here
_cgo_export.c:176:6: error: conflicting types for ‘ext_print_num’
 void ext_print_num(void* p0, GoInt64 p1)
      ^~~~~~~~~~~~~
In file included from _cgo_export.c:4:0:
wasmer.go:9:14: note: previous declaration of ‘ext_print_num’ was here
FAIL	github.com/ChainSafe/gossamer/runtime [build failed]

Additional context

Also, just wondering if you have a gitter or some other channel I can reach you on. Thanks :)

Summary

If I am running multiple independent wasmer instances concurrently in separate goroutines, can those goroutines safely call wasmer.GetLastError() and trust that they will return the error relevant to their local instance?

For example, say I have multiple goroutine's doing the following. Can errStr be relied on?

func runWasm() {
    // load a Module from some wasm called mod
...

    i, _ := mod.Instantiate()
    v, err := i.Exports["run"]
    if err != nil {
        errStr, _ := wasmer.GetLastError()
        panic(errStr)
    }
    ...
}

Thanks for the bug report!

Describe the bug

when I build wasm with go and wasm.NewInstance from the wasm bin, error result with:

Failed to compile the module.

A clear and concise description of what the bug is.

Steps to reproduce

1. build wasm with go GOARCH=wasm GOOS=js go build -o wa.wasm wa.go cat wa.go:

package main

//export Sum
func Sum(x, y int) int {
	return x + y
}

func main() {
}

2. build go program go build main.go cat main.go:

package main

import (
	"fmt"
	wasm "github.com/wasmerio/go-ext-wasm/wasmer"
)

func main() {
	bytes, err := wasm.ReadBytes("wa.wasm");
	if err != nil{
		fmt.Println(err);
		return
	}
	inst, err := wasm.NewInstance(bytes);
	if err != nil{
		fmt.Println(err);
		return
	}
	defer inst.Close();

	sum := inst.Exports["sum"]

	result, err := sum(5,37);
	if err != nil{
		fmt.Println(err);
		return;
	}
	fmt.Println(result);
}

3. Run

./main

4. See error Failed to compile the module.

Describe the bug

Memory usage slowly builds up when calling wasm module functions causing our containers to go OOM.

Steps to reproduce

I've updated the demo repository at https://github.com/Polygens/wasmer-leak to reproduce the problem with wasmer 1.0. More info in the readme.

Expected behavior

After every iteration of the for loop in the demo repo I would expect memory usage to remain consistent. If we run the demo with a single iteration it uses around 28MB. Or at least garbage collected before going OOM.

Actual behavior

Instead of memory being released after every iteration it builds up and gets OOM killed.

Additional context

We just upgraded to 1.0 to make use of the new traps :heart: but now we have an issue with the wasm functions taking too much memory. Not sure if this was present before 1.0, we had a similar issue with wasm instantiation but that seems unrelated.

Summary

How to import and use WASM that was generated from Go code?

Additional details

Given that the examples in the README are somewhat a bit more convoluted, with some rust bits in between, I am still unsure whether this library is supposed to enable the use of WASM code that was actually generated from (pure) Go.

For example, if I have:

package main

import "fmt"

func Hello() {
	fmt.Println("Hello, WebAssembly!")
}

func main() {
	fmt.Println("Hello, WebAssembly!")
}

that I build as:

GOOS=js GOARCH=wasm go build -o ./hello.wasm

and that I want to use it in another program, such as:

package main

import (
	"log"

	"github.com/wasmerio/go-ext-wasm/wasmer"
)

func main() {
	// Reads the WebAssembly module as bytes.
	bytes, err := wasmer.ReadBytes("./hello.wasm")
	if err != nil {
		log.Fatal(err)
	}

	// Instantiates the WebAssembly module.
	instance, err := wasmer.NewInstance(bytes)
	if err != nil {
		log.Fatal(err)
	}
	defer instance.Close()

	hello := instance.Exports["Hello"]
	hello()
}

then I get:

go run ./main.go
2020/04/08 14:14:32 Failed to instantiate the module:
    21 link errors: (1 of 21) Import not found, namespace: go, name: debug (2 of 21) Import not found, namespace: go, name: runtime.resetMemoryDataView (3 of 21) Import not found, namespace: go, name: runtime.wasmExit (4 of 21) Import not found, namespace: go, name: runtime.wasmWrite (5 of 21) Import not found, namespace: go, name: runtime.nanotime1 (6 of 21) Import not found, namespace: go, name: runtime.walltime1 (7 of 21) Import not found, namespace: go, name: runtime.scheduleTimeoutEvent (8 of 21) Import not found, namespace: go, name: runtime.clearTimeoutEvent (9 of 21) Import not found, namespace: go, name: runtime.getRandomData (10 of 21) Import not found, namespace: go, name: syscall/js.finalizeRef (11 of 21) Import not found, namespace: go, name: syscall/js.stringVal (12 of 21) Import not found, namespace: go, name: syscall/js.valueGet (13 of 21) Import not found, namespace: go, name: syscall/js.valueSet (14 of 21) Import not found, namespace: go, name: syscall/js.valueIndex (15 of 21) Import not found, namespace: go, name: syscall/js.valueSetIndex (16 of 21) Import not found, namespace: go, name: syscall/js.valueCall (17 of 21) Import not found, namespace: go, name: syscall/js.valueNew (18 of 21) Import not found, namespace: go, name: syscall/js.valueLength (19 of 21) Import not found, namespace: go, name: syscall/js.valuePrepareString (20 of 21) Import not found, namespace: go, name: syscall/js.valueLoadString (21 of 21) Import not found, namespace: go, name: syscall/js.copyBytesToJS
exit status 1

Is this expected? If yes, is there a way to achieve what I'm trying to do? From what I gathered in the official documentation (https://github.com/golang/go/wiki/WebAssembly) it seemed to me that WASM code that was generated from Go needed a javascript environment to run so I wouldn't expect go-ext-wasm to be able to handle it without embedding Node.js or something like that, but maybe I misunderstood?

Using go-wasmer we were able to handle Rust code by calling extern function.

can we do same for C codes? is it compatible now?

If yes. How can we call C code as an extern function?

Summary

I need to pass some byte[] array in addition to a few other values as my Context data. The unsafe Pointer thing with CGO seems to limit passing pointers with things other that value types.

Do you know of a workaround to allow passing more complex context object around.

func sum(context unsafe.Pointer, x int32, y int32) int32 {
	return x + y
}

func Test3()  {
	bytes, err := wasm1.ReadBytes("/Users/andy/Downloads/imported_function.wasm")
	if err != nil {
		fmt.Println(err)
	}
	imports, err := wasm1.NewImports().Append("sum", sum, C.sum)
	if err != nil {
		fmt.Println(err)
	}

	instance, _ := wasm1.NewInstanceWithImports(bytes, imports)

	// Close the WebAssembly instance later.
	defer instance.Close()

	// Gets the `add1` exported function from the WebAssembly instance.
	add1 := instance.Exports["add1"]

	// Calls that exported function.
	// As a reminder: `add1` is defined as `fn add1(x: i32, y: i32) -> i32 { sum(x, y) + 1 }`
	result, _ := add1(1, 2)

	// Should output 4 (= 1 + 2 + 1).
	fmt.Println(result)
}

could not determine kind of name for C.sum

Edit from @Hywan: Markup.

Summary

I enabled threads and shared memory for my AssemblyScript module and it compiles fine, but when I try to use it in wasmer it says threads must be enabled. I can't seem to find any options for this. Am I missing something or is this a bug?

Additional details

My error: 2023/01/03 17:26:13 failed to create WASM module: Validation error: threads must be enabled for shared memories (at offset 112) exit status 1

Describe The Bug

The library works fine unless I vendor, in which case the build fails

Steps To Reproduce

1. Create project using the library
2. go mod vendor
3. build the project

Expected Behavior

Successful build

Actual Behavior

/usr/local/go/pkg/tool/darwin_arm64/link: running clang failed: exit status 1 ld: warning: directory not found for option '-L/<PATH TO DIRECTORY>/vendor/github.com/wasmerio/wasmer-go/wasmer/packaged/lib/darwin-aarch64' ld: library not found for -lwasmer clang: error: linker command failed with exit code 1 (use -v to see invocation)

Bumps thiserror from 1.0.26 to 1.0.38.

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

Thanks for the bug report!

Describe the bug

I have written a simple Go module with a simple function and generated a .wasm file via the Go compiler. While loading the same .wasm file in another Go module, the NewInstance() function returns an error:

Missing import: `go`.`debug`

Expected behavior

The NewInstance() function should return a value of type *wasmer.Instance and nil as error.

Actual behavior

The NewInstance function returns nil as the primary value instead of *wasmer.Instance variable. And the error is returned to be:

Missing import: `go`.`debug`

The exact line is:

instance, err := wasmer.NewInstance(module, importObject)

Thanks for the bug report!

Describe the bug

I start a go routine, the go routine call the wasm function, then i stop the wasm instance, then it panic.

Steps to reproduce

1. Build a wasm binary by the code

EMSCRIPTEN_KEEPALIVE char* loop(int i) {
    while(true) {
        printf("%d\n", i);
    }
    return NULL;
}

2. load the wasm binary and get the NativeFunction loop

go func() {
		_, err := loop(int32(i))
		fmt.Printf("err=%v\n", err)
	}()
	time.Sleep(time.Second * 1)
	wasmStruct.instance.Close()

4. run the code
5. See error

fatal error: unexpected signal during runtime execution
[signal SIGSEGV: segmentation violation code=0x2 addr=0x298514c2c pc=0x101720a30]

runtime stack:
runtime.throw({0x1004da2e0?, 0x298000000?})
        /go1.18.4/src/runtime/panic.go:992 +0x50
runtime.sigpanic()
        /go1.18.4/src/runtime/signal_unix.go:802 +0x1e8

goroutine 34 [syscall]:
runtime.cgocall(0x1004ce1a4, 0x14000418548)
        /go1.18.4/src/runtime/cgocall.go:157 +0x54 fp=0x14000418510 sp=0x140004184d0 pc=0x10034ff94
github.com/wasmerio/wasmer-go/wasmer._Cfunc_wasm_func_call(0x6000003ccdc0, 0x14000012530, 0x14000012520)
        _cgo_gotypes.go:1235 +0x3c fp=0x14000418540 sp=0x14000418510 pc=0x1004176dc
github.com/wasmerio/wasmer-go/wasmer.(*Function).Native.func1.5(0x14000012530?, 0x0?, 0x1400001e150?)
        /pkg/mod/github.com/wasmerio/[email protected]/wasmer/function.go:317 +0xcc fp=0x14000418590 sp=0x14000418540 pc=0x10041d6cc
github.com/wasmerio/wasmer-go/wasmer.(*Function).Native.func1({0x14000012510, 0x1, 0x1004d1041?})
        /pkg/mod/github.com/wasmerio/[email protected]/wasmer/function.go:317 +0x2e8 fp=0x14000418740 sp=0x14000418590 pc=0x10041d1e8
script_myself/wasmer.ExecuteLoop.func1()
       loop.go:21 +0xb4 fp=0x140004187d0 sp=0x14000418740 pc=0x1004cd674
runtime.goexit()
        /go1.18.4/src/runtime/asm_arm64.s:1263 +0x4 fp=0x140004187d0 sp=0x140004187d0 pc=0x1003ac844
created by script_myself/wasmer.ExecuteLoop
        loop.go:20 +0x70

goroutine 1 [sleep]:
time.Sleep(0x12a05f200)
        /go1.18.4/src/runtime/time.go:194 +0x11c

exit status 2

Expected behavior

the NativeFunction loop stop print.

Actual behavior

panic

Summary

happen error

GetFunction Missing 4 argument(s) when calling the function; Expected 5 argument(s), received 1

Additional details

I use the code to build wasm by tinygo.

package main

func main() {
}

//go:export add
func Add(a, b int) int {
	return a + b
}

//go:export replace
func Replace(a string) string {
	return a + "..."
}

go code

package main

import (
	"fmt"
	"io/ioutil"

	wasmer "github.com/wasmerio/wasmer-go/wasmer"
)

func main() {
	wasmBytes, _ := ioutil.ReadFile("module.wasm")

	engine := wasmer.NewEngine()
	store := wasmer.NewStore(engine)

	// Compiles the module
	module, err := wasmer.NewModule(store, wasmBytes)
	if err != nil {
		panic(err)
	}

	wasiEnv, _ := wasmer.NewWasiStateBuilder("wasi-program").CaptureStdout().CaptureStderr().Finalize()

	importObject, err := wasiEnv.GenerateImportObject(store, module)
	if err != nil {
		panic(err)
	}
	instance, err := wasmer.NewInstance(module, importObject)
	if err != nil {
		panic(err)
	}

	addfunc, _ := instance.Exports.GetFunction("add")
	result, _ := addfunc(1, 3)
	fmt.Println(result)

	replace, _ := instance.Exports.GetFunction("replace")
	result, err = replace("aaa")
	fmt.Println(result, err)
}

the function add run successfully, but function replace failed to run.

4
<nil> Missing 4 argument(s) when calling the function; Expected 5 argument(s), received 1