I like the idea - perhaps call it PKGSRC_OVERRIDE_MKPIE? (i.e. leading
"PKGSRC_" and the s/AUTOMATIC/OVERRIDE/) - might be useful for some of
the other packages that require handholding in this area.
On 2022年1月16日 at 05:18, PHO <pho%cielonegro.org@localhost
<mailto:pho%cielonegro.org@localhost>> wrote:
Hello,
While trying to update lang/ghc90 to 9.0.2 and also enabling support
for
PKGSRC_MKPIE, I found the way how the current infrastructure enforces
MKPIE rather cumbersome for packages that need to bootstrap from a
pre-built bootkit.
GHC bootkits consist of a compiler executable and the standard Haskell
library in the form of a set of static archives (lib*.a), which may or
may not be built with -fPIC. When lang/ghc90 is to be built, with
MKPIE_SUPPORTED set to yes, one of these things will happen:
1. Bootkit is built without -fPIC, and PKGSRC_MKPIE is set to no.
This builds non-PIE GHC fine.
2. Bootkit is built with -fPIC, and PKGSRC_MKPIE is set to yes.
This builds PIE GHC fine (with some tweaks applied to
lang/ghc90).
3. Bootkit is built without -fPIC but PKGSRC_MKPIE is set to yes.
This fails to build the stage-1 compiler, which is an
intermediate
compiler to build the final, stage-2 compiler that will be installed.
This is because pkgsrc forces -pie to be passed to the linker
regardless
of compilation stages (because it doesn't know GHC does a 2-stage
bootstrapping), but the stage-1 compiler needs to be linked against
static libraries coming from the non-PIC bootkit.
4. Bootkit is built with -fPIC but PKGSRC_MKPIE is set to no.
This means we have no choice but to link a non-PIC stage-1
compiler *.o against static libraries from the bootkit built with
-fPIC.
This apparently works, at least on NetBSD, but... you aren't
supposed to
do that right? I don't know if this works on all the platforms we
currently support.
So, in order for packages like GHC to support MKPIE, we need a way to
tell pkgsrc that we are going to build PIE on our own responsibility
but
not getting enforced by the infrastructure, such as injecting -pic in
linker flags, on per-package basis. But this of course means packages
that request an exemption from the enforcement can accidentally install
non-PIE, so a post-build check is desired.
The attached patch introduces a new package-settable variable
AUTOMATIC_MKPIE and a new check mentioned above. What do you think? Can
I commit this?