Hello, I think the issue is that the libguile.h file does not help downstream packages isolate themselves from libgc completely. There are many static functions related to bdwgc in gc-inline.h, which will be combined with downstream code as a whole to compile, similar to using gc directly in your code.
Best regards On Sat, Oct 5, 2024, 21:08 Tomas Volf <~@wolfsden.cz> wrote: > > Hello, > > this might be obvious to some, but I am curious why guile puts -lgc to > the linker flags: > > --8<---------------cut here---------------start------------->8--- > $ guile-config link > -L/gnu/store/mfkz7fvlfpv3ppwbkv0imb19nrf95akf-guile-3.0.9/lib > -L/gnu/store/pr73chdirm3jc2j7npc6hqzmcwjs7l8m-libgc-8.2.4/lib -lguile-3.0 > -lgc -lpthread -ldl > --8<---------------cut here---------------end--------------->8--- > > Why is it necessary? My guile extension interacts only with the > libguile, no? Even the GC-related functions are called via their scm_ > interface, I am never directly interacting with the Boehm GC. I even > thought that the fact that Boehm GC is used is an implementation detail, > not an ABI thing. > > I would have thought that just libguile linking with the libgc is > enough, but I am far from expert in this area. So I would appreciate if > someone could enlighten me. > > (I am not sure about the -lpthread and -ldl neither, but the -lgc is the > one that caused me some problems, so I am asking about that one.) > > Thanks and have a nice day, > Tomas > > PS: So once we switch to whippet, all extensions will need to be rebuilt > due to linking against -lgc, which will no longer be Guile's dependency? > So I guess .so version bump will be used for that? > > -- > There are only two hard things in Computer Science: > cache invalidation, naming things and off-by-one errors. >
