utils: polyfill addr/unsafeAddr distinction in Nim 2+

I wish they didn't change this.  unsafeAddr may be a confusing name,
but it's more powerful than addr.  Merging them violates the principle
of least power.

e.g. say I get n thru a param, and shadow it

proc x(n: int) =
  var n = n + 1

a screen or two later I call

  mutates_variable_in_c(addr i)

then later I no longer need to add 1, so I remove the var line.

In Nim 1.6 the compiler refuses to compile, I can instantly find the
bug.  In 2.0 it does... whatever?? Maybe for an int it "works", for an
object it likely doesn't.  Certainly not something I'd enjoy debugging.

1 files changed, 1 insertions, 0 deletions

diff --git a/nim.cfg b/nim.cfg
index 8d688ac0..1dc64525 100644
--- a/nim.cfg
+++ b/nim.cfg
@@ -6,6 +6,7 @@
 --experimental:"overloadableEnums"
 --warning:Effect:off
 --mm:refc
+--include:"utils/myaddr"
 --import:"utils/eprint"
 --styleCheck:usages
 --styleCheck:hint