Re: GO on macOS Monterrey

[Jason Bacon <jtocino%gmx.com@localhost>]

On 3/5/22 17:19, Roland Illig wrote:
> Am 05.03.2022 um 22:35 schrieb Jason Bacon:
> > I don't think there's a problem here.  ${OPSYS} == "Darwin" is checked
> > first, and if that's false, ${OSX_VERSION:R} >= 12 need not be
> > evaluated, so it doesn't matter if OSX_VERSION is empty.  I just tested
> > on NetBSD and it works as expected (builds go14).
>
> The bmake from pkgsrc is from 2020-05-24, which means that it always
> evaluates ${OSX_VERSION}, even if ${OPSYS} is not "Darwin".  This has
> been fixed in NetBSD 10's make.
>
> To demonstrate this:
>
> $ cat <<'EOF' > macos.mk
> .if ${OPSYS} == Darwin && ${OSX_VERSION:U0.0:R} >= 12
> .endif
> EOF
>
> $ OPSYS=NetBSD bmake -r -f macos.mk -dcv
> ...
> lhs = "NetBSD", rhs = "Darwin", op = ==
> Applying[OSX_VERSION] :U to ""
> Result[OSX_VERSION] of :U is "0.0"
> Applying[OSX_VERSION] :R to "0.0"
> Result[OSX_VERSION] of :R is "0"
> left = 0.000000, right = 12.000000, op = >=
> ...
>
> On NetBSD 10, the debug log has a different format but is still roughly
> comparable:
>
> $ OPSYS=NetBSD /usr/bin/make -r -f macos.mk -dcv
> ...
> CondParser_Eval: ${OPSYS} == Darwin && ${OSX_VERSION:U0.0:R} >= 12
> Var_Parse: ${OPSYS} == Darwin && ${OSX_VERSION:U0.0:R} >= 12 (eval-defined)
> Comparing "NetBSD" == "Darwin"
> Var_Parse: ${OSX_VERSION:U0.0:R} >= 12 (parse-only)
> Parsing modifier ${OSX_VERSION:U...}
> Result of ${OSX_VERSION:U0.0} is "" (parse-only, defined)
> Parsing modifier ${OSX_VERSION:R}
> Result of ${OSX_VERSION:R} is "" (parse-only, defined)
> ...
>
> The log output does not have a line for "Comparing 12.000000" now.
> Furthermore, it clearly says that the second condition is parse-only, it
> is not evaluated.
>
>
> Be careful though if OSX_VERSION can have three parts, for example
> 12.0.0.  In such a case, the modifier ':R' would only strip the last
> component, leaving 12.0.  This can be compared numerically, and in the
> edge case of having version numbers like 12.10.3, this number would be
> less than 12.2.3, simply because 12.100000 < 12.200000.  When comparing
> with 12.0, this is no problem though.
>
> To get only the major version even in case of three-part version
> numbers, use ':R' twice, resulting in ${OSX_VERSION:R:R}.
>
> Roland

Interesting, thanks for the detailed explanation.

A variation on that shows that an empty variable evaluates to 0.0 in 
this setting:

NetBSD netbsd9.acadix  bacon ~ 1014: (pkgsrc): cat macos.mk 
        .if ${OPSYS} == Darwin && ${OSX_VERSION:R} >= 12
.endif
NetBSD netbsd9.acadix  bacon ~ 1015: (pkgsrc): env OPSYS=NetBSD bmake -r 
-f macos.mk -dcv

[snip]

Applying[OSX_VERSION] :R to ""
Result[OSX_VERSION] of :R is ""
left = 0.000000, right = 12.000000, op = >=

So it's safe for non-Darwin platforms and adding :U seems to have no effect.

To assess the situation on Darwin, I added the following to a pkg Makefile:

do-configure:
        @echo ${OPSYS}
        @echo ${OSX_VERSION} ${OSX_VERSION:R} ${OSX_VERSION:R:R}

bmake configure produces:

Darwin
12.2 12 12

So the :R:R syntax is safe with a 2-part version, which was the only 
question left in my mind following Roland's tips.

Assuming OSX_VERSION will never have *four* parts, I would go with the 
following:

--- bootstrap.mk        14 Jul 2021 14:32:04 -0000      1.7
+++ bootstrap.mk        6 Mar 2022 00:19:22 -0000
@@ -1,7 +1,7 @@
 # $NetBSD: bootstrap.mk,v 1.7 2021/07/14 14:32:04 jperkin Exp $

 .if !defined(GOROOT_BOOTSTRAP) || !exists(${GOROOT_BOOTSTRAP}/bin/go)
-.  if ${MACHINE_ARCH} == "aarch64"
+.  if ${MACHINE_ARCH} == "aarch64" || ${OPSYS} == "Darwin" && 
${OSX_VERSION:R:R} >= 12
 BUILD_DEPENDS+=                go-bin-[0-9]*:../../lang/go-bin
 GOROOT_BOOTSTRAP=      ${PREFIX}/go-bin
 .  else