What version of Go are you using (go version)?

$ go version
version go1.16.4 linux/386

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

$ go env
GO111MODULE=""
GOARCH="386"
GOBIN=""
GOCACHE="/root/.cache/go-build"
GOENV="/root/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="386"
GOHOSTOS="linux"
GOINSECURE="golang.org,googlesource.com"
GOMODCACHE="/home/nilesh/golang/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/nilesh/golang"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/linux_386"
GOVCS=""
GOVERSION="go1.16.4"
GCCGO="gccgo"
GO386="sse2"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/home/nilesh/SVN/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m32 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build718813889=/tmp/go-build -gno-record-gcc-switches"

What did you do?

See Go definition of CheckConnection() function given below. I exported CheckConnection Go function as C function in .so file using following command.
go build -o mygolib.so -buildmode=c-shared mygolib.go

Then using generated .SO and .h, called exported Go function from my C test program. Below is the command I used to compile and build my C test program.

gcc -o testclient testclient.c ./mygolib.so

With this testclient program in C I am able to get the response from myClient. However when I included this .so and .h file in our existing Linux service (in C only),I am unable to make http request. Below is my Go function. Call gets blocked at below line, does not timeout or gives any error. testclient and linux service is on same machine. However from testclient function returns me the response but from linux service call gets hang.

res,err := myClient.Do(req)

//export CheckConnection
func CheckConnection() {

reqUrl,_ := url.Parse("https://www.google.com/")

req := &http.Request{
Method: "GET",
URL: reqUrl,
Header: map[string][]string{
"Content-type": {"application/json; charset=UTF-8" },
},
}

 var myClient = &http.Client{
  Timeout: time.Second * 10,
 }

res,err := myClient.Do(req)
if err!= nil {
log.Fatal("Error ",err)
}

data,_ := ioutil.ReadAll(res.Body)
res.Body.Close()

log.Print("Resp code ",res.StatusCode)
log,Print("Data ",data)
}

What did you expect to see?

res,err := myClient.Do(req)
Above call should either return me the response string or timeout error.

What did you see instead?

Call gets hand on below code line -
res,err := myClient.Do(req)