Why is a Deadlock Error Not Returned in this Code?

The code provided imports the net/http package, which initializes Goroutines that perform background polling. This inadvertently disables the deadlock detector, preventing the expected deadlock error from being returned.

To understand this behavior, consider the code excerpt:

package main

import (
    "fmt"
    "net/http"
)

func main() {
    var ch = make(chan int)
    ch 
In this case, the main function creates a channel and sends a value into it, potentially causing a deadlock. However, since the net/http package has been imported, the deadlock detector is disabled and no error is returned.
If the import is removed:
package main

import "fmt"

func main() {
    var ch = make(chan int)
    ch 
The deadlock error is now correctly returned because the background polling Goroutines are not active.
This behavior is consistent with the discussion in the GitHub issue: https://github.com/golang/go/issues/12734, where it is explained that importing the net/http package disables the deadlock detector.