diff --git a/src/runtime/cgocall.go b/src/runtime/cgocall.go
index 7cffa83617..d5248803a4 100644
--- a/src/runtime/cgocall.go
+++ b/src/runtime/cgocall.go
@@ -113,11 +113,6 @@ func cgocall(fn, arg unsafe.Pointer) int32 {
 	mp.ncgo++
 	defer endcgo(mp)
 
-	// Allocate memory to hold a cgo traceback if the cgo call crashes.
-	if mp.cgoCallers == nil {
-		mp.cgoCallers = new(cgoCallers)
-	}
-
 	// Reset traceback.
 	mp.cgoCallers[0] = 0
 
diff --git a/src/runtime/proc.go b/src/runtime/proc.go
index 27e61bd3e2..1e1987ff9e 100644
--- a/src/runtime/proc.go
+++ b/src/runtime/proc.go
@@ -510,6 +510,11 @@ func mcommoninit(mp *m) {
 	// so we need to publish it safely.
 	atomicstorep(unsafe.Pointer(&allm), unsafe.Pointer(mp))
 	unlock(&sched.lock)
+
+	// Allocate memory to hold a cgo traceback if the cgo call crashes.
+	if iscgo || GOOS == "solaris" || GOOS == "windows" {
+		mp.cgoCallers = new(cgoCallers)
+	}
 }
 
 // Mark gp ready to run.