v3.1/gles2: installing GLES2 shows "fatal error: KHR/khrplatform.h: No such file or directory"

[zzador]

Tried to download & install GLES2 with go get -u github.com/go-gl/gl/v3.1/gles2. Git the following error: fatal error: KHR/khrplatform.h: No such file or directory.

Im using GO 1.14.2 with MinGW GCC 8.1.0. All correctly installed.

The file "khrplatform.h" does simply not exist within the include directories of GCC.

[ltto]

meto OS:MacOS 10.15.7 GO:1.14.7

go/src/github.com/go-gl/gl/v3.1/gles2/package.go:38:11: fatal error: 'KHR/khrplatform.h' file not found
 #include <KHR/khrplatform.h>
          ^~~~~~~~~~~~~~~~~~~
1 error generated.

[einthusan]

Bump! I am having the same exact error. I know macOS by default does not support GLES2 but using google/ANGLE this should have faux support. I will try to compile ANGLE for macOS and report back.

[einthusan]

Having some difficulties trying to get ANGLE to work. https://github.com/go-gl/glow/issues/51#issuecomment-766287296

[zwang]

I am able to get this works with Google/ANGLE. What I did is to set the CFlags and LDFlags like this:

CGO_CFLAGS=-I/Users/zhao/workspace/angle/include CGO_LDFLAGS=-L/Users/zhao/workspace/angle/out/Release

In /Users/zhao/workspace/angle/out/Release it contains these two libs: libEGL.dylib and libGLESv2.dylib

Here is the PR to allow building go-gl/gl with tags on macOS: https://github.com/go-gl/gl/pull/134

Similar to windows, also need to set the flags above and link to libEGL.dll, libGLESv2.dll and d3dcompiler_47.dll

Here is the related PR for windows: https://github.com/go-gl/gl/pull/133

Note: this is for the Intel Mac. I failed to build ANGLE with M1 Mac.

[einthusan]

@zwang wow thanks! I will try it out when I get a chance and write back with my results.

[einthusan]

@zwang I managed to build it after several hours of messing with go mod and KHR deps. EDIT: I ended up copying the entire KHR directory to the path pointed to by CGO_CFLAGS cp -r /usr/local/gopath/src/github.com/go-gl/glfw/v3.1/glfw/glfw/deps/KHR /Users/username/workspace/angle/include/

But i get the following error. Please help 😅 EDIT: https://github.com/glfw/glfw/issues/1169

test20-vbo: go build
test20-vbo: go run .
2021/04/25 16:27:12 PlatformError: EGL: Failed to create window surface: A NativeWindowType argument does not refer to a valid native window
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x40c0022]

goroutine 1 [running, locked to thread]:
github.com/pb/example/vendor/github.com/go-gl/glfw/v3.3/glfw.(*Window).MakeContextCurrent.func1(0x0)
    /usr/local/gopath/src/github.com/pb/example/vendor/github.com/go-gl/glfw/v3.3/glfw/context.go:17 +0x22
github.com/pb/example/vendor/github.com/go-gl/glfw/v3.3/glfw.(*Window).MakeContextCurrent(0x0)
    /usr/local/gopath/src/github.com/pb/example/vendor/github.com/go-gl/glfw/v3.3/glfw/context.go:17 +0x2b
main.main()
    /usr/local/gopath/src/github.com/pb/example/gles20-cube/test20-vbo/triangle.go:52 +0x1a0
exit status 2

EDIT: If i remove the following hint/line from my code glfw.WindowHint(glfw.ClientAPI, glfw.OpenGLESAPI), then i get the following error.

GLFW: An invalid error was not accepted by the caller: FormatUnavailable: EGL: Failed to find a suitable EGLConfig
GLFW: Please report this bug in the Go package immediately.
panic: FormatUnavailable: EGL: Failed to find a suitable EGLConfig

goroutine 1 [running, locked to thread]:
github.com/pb/example/vendor/github.com/go-gl/glfw/v3.3/glfw.acceptError(0xc000040e98, 0x2, 0x2, 0x0, 0x0)
    /usr/local/gopath/src/github.com/pb/example/vendor/github.com/go-gl/glfw/v3.3/glfw/error.go:178 +0x201
github.com/pb/example/vendor/github.com/go-gl/glfw/v3.3/glfw.CreateWindow(0x258, 0x190, 0x4150ef0, 0xb, 0x0, 0x0, 0x0, 0x0, 0x0)
    /usr/local/gopath/src/github.com/pb/example/vendor/github.com/go-gl/glfw/v3.3/glfw/window.go:350 +0x1aa
main.main()
    /usr/local/gopath/src/github.com/pb/example/gles20-cube/test20-vbo/triangle.go:48 +0x156
exit status 2

[einthusan]

It seems that on OSX, cgo is igorning the CGO_LDFLAGS.

Setting the env variable export DYLD_LIBRARY_PATH=/Users/username/workspace/angle/out/Release does not help. Btw, for anyone reading this, DYLD_LIBRARY_PATH is the mac equivalent of LD_LIBRARY_PATH in linux.

I also ran go build -a with -a flag to ensure a proper full rebuild was taking place with cgo. Just in case, I also used go clean -cache -testcache . to clear any caches, but still same problem.

The mac equivalent of linux's ldd is otool -L. I used this to inspect the built go binary of my project. I noticed that it was picking up a slightly older version of some libraries. So I went ahead and deleted all the libs under /Users/username/workspace/angle/out/Release and tried a rebuild, hoping that it would fail, saying the libs are not found. But to my surprise, it builds successfully.

This is why I believe cgo is ignoring the CGO_LDFLAGS and finding some older version of these libs somewhere in my system.

EDIT: The question still remains, does it matter that an older version is found? I think it does. One of the libs in my system has reference to Metal, the other does not. See below for the 2 outputs.

otool -L test20-vbo 
test20-vbo:
    /System/Library/Frameworks/OpenGL.framework/Versions/A/OpenGL (compatibility version 1.0.0, current version 1.0.0)
    /System/Library/Frameworks/Cocoa.framework/Versions/A/Cocoa (compatibility version 1.0.0, current version 22.0.0)
    /System/Library/Frameworks/IOKit.framework/Versions/A/IOKit (compatibility version 1.0.0, current version 275.0.0)
    /System/Library/Frameworks/CoreVideo.framework/Versions/A/CoreVideo (compatibility version 1.2.0, current version 1.5.0)
    /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1226.10.1)
    /System/Library/Frameworks/AppKit.framework/Versions/C/AppKit (compatibility version 45.0.0, current version 1404.47.0)
    /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation (compatibility version 150.0.0, current version 1259.22.0)
    /System/Library/Frameworks/CoreGraphics.framework/Versions/A/CoreGraphics (compatibility version 64.0.0, current version 600.0.0)
    /System/Library/Frameworks/CoreServices.framework/Versions/A/CoreServices (compatibility version 1.0.0, current version 728.14.0)
    /System/Library/Frameworks/Foundation.framework/Versions/C/Foundation (compatibility version 300.0.0, current version 1259.32.0)
    /usr/lib/libobjc.A.dylib (compatibility version 1.0.0, current version 228.0.0)

This has reference to metal.

otool -L "/Applications/Google Chrome.app/Contents/Frameworks/Google Chrome Framework.framework/Versions/89.0.4389.128/Libraries/libGLESv2.dylib"
/Applications/Google Chrome.app/Contents/Frameworks/Google Chrome Framework.framework/Versions/89.0.4389.128/Libraries/libGLESv2.dylib:
    ./libGLESv2.dylib (compatibility version 0.0.0, current version 0.0.0)
    /System/Library/Frameworks/Metal.framework/Versions/A/Metal (compatibility version 1.0.0, current version 244.32.6)
    /System/Library/Frameworks/Foundation.framework/Versions/C/Foundation (compatibility version 300.0.0, current version 1770.106.0)
    /System/Library/Frameworks/IOKit.framework/Versions/A/IOKit (compatibility version 1.0.0, current version 275.0.0)
    /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation (compatibility version 150.0.0, current version 1770.106.0)
    /System/Library/Frameworks/CoreGraphics.framework/Versions/A/CoreGraphics (compatibility version 64.0.0, current version 1463.0.0)
    /System/Library/Frameworks/OpenGL.framework/Versions/A/OpenGL (compatibility version 1.0.0, current version 1.0.0)
    /System/Library/Frameworks/IOSurface.framework/Versions/A/IOSurface (compatibility version 1.0.0, current version 1.0.0)
    /System/Library/Frameworks/QuartzCore.framework/Versions/A/QuartzCore (compatibility version 1.2.0, current version 1.11.0)
    /System/Library/Frameworks/Cocoa.framework/Versions/A/Cocoa (compatibility version 1.0.0, current version 23.0.0)
    /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1292.0.0)
    /usr/lib/libobjc.A.dylib (compatibility version 1.0.0, current version 228.0.0)

[einthusan]

Some more update. If you run build with -x flag, you get more verbose output of the cgo process. go build -a -x

I noticed that -framework OpenGL was being added to the CGO_LDFLAGS ... i suspect this to be the problem, maybe a conflict with this package?

cd /usr/local/gopath/src/github.com/go-gl/gl/v3.1/gles2
  1 CGO_LDFLAGS='"-L/Users/username/workspace/angle/out/Release" "-framework" "OpenGL" "-framework" "OpenGL"' /usr/local/go/pkg/tool/darwin_amd64/cgo -o
  2 /usr/local/go/pkg/tool/darwin_amd64/buildid -w $WORK/b042/_pkg_.a # internal
  3 cp $WORK/b042/_pkg_.a /Users/username/Library/Caches/go-build/87/876ebdd267ab8b9acdbab20da2958b742c2517b376fa8181c2de01eae0cc7df2-d # internal
  4 mkdir -p $WORK/b035/
  5 cd /usr/local/gopath/src/github.com/pb/example/vendor/github.com/go-gl/glfw/v3.3/glfw
  6 CGO_LDFLAGS='"-L/Users/username/workspace/angle/out/Release" "-framework" "Cocoa" "-framework" "OpenGL" "-framework" "IOKit" "-framework" "CoreVideo
  7 cd $WORK/b032
  8 TERM='dumb' clang -I /usr/local/gopath/src/github.com/go-gl/gl/v3.1/gles2 -fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-len
  9 TERM='dumb' clang -I /usr/local/gopath/src/github.com/go-gl/gl/v3.1/gles2 -fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-len
 10 TERM='dumb' clang -I /usr/local/gopath/src/github.com/go-gl/gl/v3.1/gles2 -fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-len
 11 TERM='dumb' clang -I /usr/local/gopath/src/github.com/go-gl/gl/v3.1/gles2 -fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-len
 12 TERM='dumb' clang -I /usr/local/gopath/src/github.com/go-gl/gl/v3.1/gles2 -fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-len
 13 TERM='dumb' clang -I /usr/local/gopath/src/github.com/go-gl/gl/v3.1/gles2 -fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-len
 14 cd /usr/local/gopath/src/github.com/go-gl/gl/v3.1/gles2
 15 TERM='dumb' clang -I . -fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=$WORK/b032=/tmp/go-build -
 16 TERM='dumb' /usr/local/go/pkg/tool/darwin_amd64/cgo -dynpackage gles2 -dynimport $WORK/b032/_cgo_.o -dynout $WORK/b032/_cgo_import.go

[einthusan]

Getting close! So after updating glfw package to latest to incorporate @zwang fixes for OpenGL ES (totally forgot to do that). I realized I was also being stupid for not using the tags flag accordingly. So this time, I ran it correctly.

go build -a -x -tags=gles2

And the output from otool was much better.

test20-vbo: otool -L test20-vbo 
test20-vbo:
    ./libGLESv2.dylib (compatibility version 0.0.0, current version 0.0.0)
    /System/Library/Frameworks/Cocoa.framework/Versions/A/Cocoa (compatibility version 1.0.0, current version 22.0.0)
    /System/Library/Frameworks/OpenGL.framework/Versions/A/OpenGL (compatibility version 1.0.0, current version 1.0.0)
    /System/Library/Frameworks/IOKit.framework/Versions/A/IOKit (compatibility version 1.0.0, current version 275.0.0)
    /System/Library/Frameworks/CoreVideo.framework/Versions/A/CoreVideo (compatibility version 1.2.0, current version 1.5.0)
    /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1226.10.1)
    /System/Library/Frameworks/AppKit.framework/Versions/C/AppKit (compatibility version 45.0.0, current version 1404.47.0)
    /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation (compatibility version 150.0.0, current version 1259.22.0)
    /System/Library/Frameworks/CoreGraphics.framework/Versions/A/CoreGraphics (compatibility version 64.0.0, current version 600.0.0)
    /System/Library/Frameworks/CoreServices.framework/Versions/A/CoreServices (compatibility version 1.0.0, current version 728.14.0)
    /System/Library/Frameworks/Foundation.framework/Versions/C/Foundation (compatibility version 300.0.0, current version 1259.32.0)
    /usr/lib/libobjc.A.dylib (compatibility version 1.0.0, current version 228.0.0)

Notice the first line, ./libGLESv2.dylib (compatibility version 0.0.0, current version 0.0.0) (this is new) but, we still have the following line, /System/Library/Frameworks/OpenGL.framework/Versions/A/OpenGL (compatibility version 1.0.0, current version 1.0.0) and it is not showing Metal like Google Chrome's libs do.

[einthusan]

FINALLY! Found the solution that works. First of all, the damn go mod is a pain in the ass, causing all sorts of problems.

1. I turned it off using export GO111MODULE="off"
2. I ensured both "github.com/go-gl/gl/v3.1/gles2" and "github.com/go-gl/glfw/v3.3/glfw" were 100% updated to latest versions. (this is where go mod was messing up)
3. then build using the correct flags go build -a -tags=gles2,egl (i missed egl last time)
4. ensure dylib and cgo flags are correctly setup (see @zwang response)
5. in desperation i put the dylib's in several places, including the local working directory and to directories where CGO_LDFLAGS and CGO_CFLAGS is pointing to.

The results from otool didn't change much, but it worked.

otool -L test20-vbo 
test20-vbo:
    ./libGLESv2.dylib (compatibility version 0.0.0, current version 0.0.0)
    ./libEGL.dylib (compatibility version 0.0.0, current version 0.0.0)
    /System/Library/Frameworks/Cocoa.framework/Versions/A/Cocoa (compatibility version 1.0.0, current version 22.0.0)
    /System/Library/Frameworks/IOKit.framework/Versions/A/IOKit (compatibility version 1.0.0, current version 275.0.0)
    /System/Library/Frameworks/CoreVideo.framework/Versions/A/CoreVideo (compatibility version 1.2.0, current version 1.5.0)
    /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1226.10.1)
    /System/Library/Frameworks/AppKit.framework/Versions/C/AppKit (compatibility version 45.0.0, current version 1404.47.0)
    /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation (compatibility version 150.0.0, current version 1259.22.0)
    /System/Library/Frameworks/CoreGraphics.framework/Versions/A/CoreGraphics (compatibility version 64.0.0, current version 600.0.0)
    /System/Library/Frameworks/CoreServices.framework/Versions/A/CoreServices (compatibility version 1.0.0, current version 728.14.0)
    /System/Library/Frameworks/Foundation.framework/Versions/C/Foundation (compatibility version 300.0.0, current version 1259.32.0)
    /usr/lib/libobjc.A.dylib (compatibility version 1.0.0, current version 228.0.0)

This is the output from my program once it worked.

OpenGL version OpenGL ES 1.1.0 (ANGLE 2.1.14675 git hash: f25a0b5b404b)

and after I changed my code to use OpenGL ES 2.0, the output is

OpenGL version OpenGL ES 3.0.0 (ANGLE 2.1.14675 git hash: f25a0b5b404b)

not sure why it says 3.0.0 even thought I only want v2.0 ... but at least it works. Thanks @zwang for getting me going on the right track.

[einthusan]

This issue can be marked as closed! @zzador @dmitshur or whoever the moderator is 👍

[changkun]

I still have a similar issue on macOS (Apple Silicon), what could be a mistake from my side?

$ go build
# github.com/go-gl/gl/v2.1/gl
../../vendor/github.com/go-gl/gl/v2.1/gl/package.go:40:11: fatal error: 'KHR/khrplatform.h' file not found
 #include <KHR/khrplatform.h>
          ^~~~~~~~~~~~~~~~~~~
1 error generated.

[changkun]

Fall back to an old version solves the issue:

diff --git a/go.mod b/go.mod
index 62291a2..510b6d6 100644
--- a/go.mod
+++ b/go.mod
 go 1.17

 require (
-       github.com/go-gl/gl v0.0.0-20210501111010-69f74958bac0
+       github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7