cmd/compile: turn off variable-sized make() stack allocation with -N

Give people a way to turn this optimization off.

(Currently the constant-sized make() stack allocation is not disabled
with -N. Kinda inconsistent, but oh well, probably worse to change it now.)

Update #73253

Change-Id: Idb9ffde444f34e70673147fd6a962368904a7a55
Reviewed-on: https://go-review.googlesource.com/c/go/+/664655
Reviewed-by: Dmitri Shuralyov <[email protected]>
Reviewed-by: Jorropo <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Keith Randall <[email protected]>
Reviewed-by: t hepudds <[email protected]>

Author: randall77

src/cmd/compile/internal/walk/builtin.go

@@ -568,7 +568,7 @@ func walkMakeSlice(n *ir.MakeExpr, init *ir.Nodes) ir.Node {
 			// The conv is necessary in case n.Type is named.
 			return walkExpr(typecheck.Expr(typecheck.Conv(s, n.Type())), init)
 		}
-		tryStack = true
+		tryStack = base.Flag.N == 0
 	}
 
 	// The final result is assigned to this variable.