How build lib for 386 arch with cgo on windows?-CodePudding

I have a golang library that builds and works well on Linux, MacOs and Windows. The problem comes when I'm trying to build it for 386 on the amd64 Windows VM. I've installed latest golang SDK and mingw, which makes amd64 build work fine, but not the 386:

PS > gcc -v
gcc.exe (MinGW-W64 x86_64-posix-seh, built by Brecht Sanders) 11.2.0

PS > go version
go version go1.18.3 windows/amd64
    
PS > $Env:GOOS = "windows"; $Env:GOARCH = "386"; $Env:CGO_ENABLED ="1"; go build -v -buildmode=c-shared -ldflags="-s -w" -gcflags="-l" -o xyz_amd64.dll xyz_win_dll.go
...
runtime/cgo
c:/programdata/chocolatey/lib/mingw/tools/install/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: skipping incompatible c:/pro
gramdata/chocolatey/lib/mingw/tools/install/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/lib/libmingwthrd.a when searching for -lmingwt
hrd
...
<a lot of skipping incompatible messages here>
collect2.exe: error: ld returned 1 exit status

How to fix it? AFAIK it should be possible to build for both arch on the same box.

CodePudding user response：

Cgo build fail, I solve it by this way: firstly, ensure build C code successfully.

generally, cgo cross compilation require C cross compilation and Go cross compilation . maybe you can add set // #cgo CFLAGS:C_CrossBuild_Parameters.

As you can see, it's not easy. It's why Cross compilation goes out the window

CodePudding user response：

I've found the diff in the project description and switched to https://www.mingw-w64.org/. It contains libs for both arch 386 and x64. Now across compilation works fine to me.