never executed always true always false

    1 module GHC.Linker
    2    (
    3    )
    4 where
    5 
    6 import GHC.Prelude ()
    7    -- We need this dummy dependency for the make build system. Otherwise it
    8    -- tries to load GHC.Types which may not be built yet.
    9 
   10 -- Note [Linkers and loaders]
   11 -- ~~~~~~~~~~~~~~~~~~~~~~~~~~
   12 --
   13 -- Linkers are used to produce linked objects (.so, executables); loaders are
   14 -- used to link in memory (e.g., in GHCi) with the already loaded libraries
   15 -- (ghc-lib, rts, etc.).
   16 --
   17 -- Linking can usually be done with an external linker program ("ld"), but
   18 -- loading is more tricky:
   19 --
   20 --    * Fully dynamic:
   21 --       when GHC is built as a set of dynamic libraries (ghc-lib, rts, etc.)
   22 --       and the modules to load are also compiled for dynamic linking, a
   23 --       solution is to fully rely on external tools:
   24 --
   25 --       1) link a .so with the external linker
   26 --       2) load the .so with POSIX's "dlopen"
   27 --
   28 --    * When GHC is built as a static program or when libraries we want to load
   29 --    aren't compiled for dynamic linking, GHC uses its own loader ("runtime
   30 --    linker"). The runtime linker is part of the rts (rts/Linker.c).
   31 --
   32 -- Note that within GHC's codebase we often use the word "linker" to refer to
   33 -- the static object loader in the runtime system.
   34 --
   35 -- Loading can be delegated to an external interpreter ("iserv") when
   36 -- -fexternal-interpreter is used.