From 99339dd44537f82c9a1348b8937b68b6c61be005 Mon Sep 17 00:00:00 2001 From: Austin Clements Date: Mon, 3 Oct 2016 11:52:20 -0400 Subject: [PATCH] runtime: weaken claim about SetFinalizer panicking Currently the SetFinalizer documentation makes a strong claim that SetFinalizer will panic if the pointer is not to an object allocated by calling new, to a composite literal, or to a local variable. This is not true. For example, it doesn't panic when passed the address of a package-level variable. Nor can we practically make it true. For example, we can't distinguish between passing a pointer to a composite literal and passing a pointer to its first field. Hence, weaken the guarantee to say that it "may" panic. Updates #17311. (Might fix it, depending on what we want to do with package-level variables.) Change-Id: I1c68ea9d0a5bbd3dd1b7ce329d92b0f05e2e0877 Reviewed-on: https://go-review.googlesource.com/30137 Reviewed-by: Brad Fitzpatrick --- src/runtime/mfinal.go | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/runtime/mfinal.go b/src/runtime/mfinal.go index b3f30dd5ae..f9344882b1 100644 --- a/src/runtime/mfinal.go +++ b/src/runtime/mfinal.go @@ -231,7 +231,7 @@ func runfinq() { // address of a local variable. // The argument finalizer must be a function that takes a single argument // to which obj's type can be assigned, and can have arbitrary ignored return -// values. If either of these is not true, SetFinalizer aborts the +// values. If either of these is not true, SetFinalizer may abort the // program. // // Finalizers are run in dependency order: if A points at B, both have