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   Haelwenn /элвэн/ :triskell: (lanodan@queer.hacktivis.me)'s status on Saturday, 29-Jun-2024 19:41:45 JST Haelwenn /элвэн/ :triskell:

   • lcamtuf :verified: :verified: :verified:
   • LEdoian
   @ledoian @lcamtuf I'd guess the interrupt handler table would be a function pointer table, which is used pretty often in C.
   Dynamic linker… I'd doubt it would be like function pointers. https://git.musl-libc.org/cgit/musl/tree/ldso at least is pretty small but I've just woke up so bit hard to tell for sure.
   
   While even just a goto to a dynamic address + label as value, I don't think I've seen that in C before.
   Although it seems like a GNU extension so I guess that could explain why: https://gcc.gnu.org/onlinedocs/gcc-4.8.0/gcc/Labels-as-Values.html#Labels-as-Values
   • Embed this notice
     LEdoian (ledoian@pleroma.ledoian.cz)'s status on Saturday, 29-Jun-2024 23:48:06 JST LEdoian

     in reply to

     • lcamtuf :verified: :verified: :verified:

     @lanodan @lcamtuf I meant, if I were to implement switch in assembly, having a table determined by labels and indirectly jumping through it would make sense (and there are already examples of such tables).

     I didn't expect that this would even work in C in any way (standard probably does not allow manipulating labels at all), though it is not surprising that GCC exposes this functionality (given many architectures support indirect jumps), TIL! I weren't aware that the original post was actually a valid gnu-c code…

     Haelwenn /элвэн/ :triskell: likes this.