Closed
Description
What version of Go are you using (go version
)?
$ go version go version devel +b388d68 Thu Jun 13 03:58:18 2019 +0000 darwin/amd64
Does this issue reproduce with the latest release?
Yes
What operating system and processor architecture are you using (go env
)?
go env
Output
$ go env GO111MODULE="" GOARCH="amd64" GOBIN="" GOCACHE="/Users/hajimehoshi/Library/Caches/go-build" GOENV="/Users/hajimehoshi/Library/Application Support/go/env" GOEXE="" GOFLAGS="" GOHOSTARCH="amd64" GOHOSTOS="darwin" GONOPROXY="" GONOSUMDB="" GOOS="darwin" GOPATH="/Users/hajimehoshi/go" GOPRIVATE="" GOPROXY="https://proxy.golang.org,direct" GOROOT="/Users/hajimehoshi/sdk/gotip" GOSUMDB="sum.golang.org" GOTMPDIR="" GOTOOLDIR="/Users/hajimehoshi/sdk/gotip/pkg/tool/darwin_amd64" GCCGO="gccgo" AR="ar" CC="clang" CXX="clang++" 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 -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/ht/ky_bwgzs4bd5z1hh02k34x_h0000gn/T/go-build197596843=/tmp/go-build -gno-record-gcc-switches -fno-common"
What did you do?
Compile this program as Wasm and run it on iOS Safari
https://play.golang.org/p/4ez7BztzRZf
package main
import (
"bytes"
"image/color"
"image/png"
)
var pngimg = []byte("\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x00 \x00\x00\x00 \b\x02\x00\x00\x00\xfc\x18\xed\xa3\x00\x00\x00\tpHYs\x00\x00\v\x13\x00\x00\v\x13\x01\x00\x9a\x9c\x18\x00\x00\x00<IDATH\xc7\xedѱ\r\x000\b\x03A\xc8J\xec\xbf\x01\x9e\xc9̀\x944\xd1\u007fmt\x05\xd9ݱ\xa9\xaaV\xfb\x13\x8f\x03\x00\x00\x00\x00\xb8Q\xda^\x1dH\xe2\a\x00\x00\x00\x00\xff\x01\x03\xd79\b\xa0\u007fq\xb3\xbb\x00\x00\x00\x00IEND\xaeB`\x82")
func main() {
img, err := png.Decode(bytes.NewReader(pngimg))
if err != nil {
panic(err)
}
println(img.At(16, 15).(color.RGBA).R, img.At(16, 15).(color.RGBA).A)
println(img.At(16, 16).(color.RGBA).R, img.At(16, 16).(color.RGBA).A)
}
What did you expect to see?
On console:
255 255
204 255
What did you see instead?
204 255
255 255
or
0 255
255 255
Note
This works correctly on any other browsers than iOS Safari, including desktop Safari.