diff options
Diffstat (limited to 'compiler/GHC/Driver/Session.hs')
| -rw-r--r-- | compiler/GHC/Driver/Session.hs | 63 |
1 files changed, 37 insertions, 26 deletions
diff --git a/compiler/GHC/Driver/Session.hs b/compiler/GHC/Driver/Session.hs index aa761325d3..fd9efaaafb 100644 --- a/compiler/GHC/Driver/Session.hs +++ b/compiler/GHC/Driver/Session.hs @@ -206,6 +206,7 @@ module GHC.Driver.Session ( -- * Linker/compiler information LinkerInfo(..), CompilerInfo(..), + useXLinkerRPath, -- * Include specifications IncludeSpecs(..), addGlobalInclude, addQuoteInclude, flattenIncludes, @@ -3680,7 +3681,8 @@ defaultFlags settings Opt_ProfCountEntries, Opt_SharedImplib, Opt_SimplPreInlining, - Opt_VersionMacros + Opt_VersionMacros, + Opt_RPath ] ++ [f | (ns,f) <- optLevelFlags, 0 `elem` ns] @@ -3688,8 +3690,6 @@ defaultFlags settings ++ default_PIC platform - ++ default_RPath platform - ++ validHoleFitDefaults where platform = sTargetPlatform settings @@ -3743,29 +3743,6 @@ default_PIC platform = -- information. _ -> [] - --- We usually want to use RPath, except on macOS (OSDarwin). On recent macOS --- versions the number of load commands we can embed in a dynamic library is --- restricted. Hence since b592bd98ff2 we rely on -dead_strip_dylib to only --- link the needed dylibs instead of linking the full dependency closure. --- --- If we split the library linking into injecting -rpath and -l @rpath/... --- components, we will reduce the number of libraries we link, however we will --- still inject one -rpath entry for each library, independent of their use. --- That is, we even inject -rpath values for libraries that we dead_strip in --- the end. As such we can run afoul of the load command size limit simply --- by polluting the load commands with RPATH entries. --- --- Thus, we disable Opt_RPath by default on OSDarwin. The savvy user can always --- enable it with -use-rpath if they so wish. --- --- See Note [Dynamic linking on macOS] - -default_RPath :: Platform -> [GeneralFlag] -default_RPath platform | platformOS platform == OSDarwin = [] -default_RPath _ = [Opt_RPath] - - -- General flags that are switched on/off when other general flags are switched -- on impliedGFlags :: [(GeneralFlag, TurnOnFlag, GeneralFlag)] @@ -4785,6 +4762,40 @@ data CompilerInfo | UnknownCC deriving Eq + +-- | Should we use `-XLinker -rpath` when linking or not? +-- See Note [-fno-use-rpaths] +useXLinkerRPath :: DynFlags -> OS -> Bool +useXLinkerRPath _ OSDarwin = False -- See Note [Dynamic linking on macOS] +useXLinkerRPath dflags _ = gopt Opt_RPath dflags + +{- +Note [-fno-use-rpaths] +~~~~~~~~~~~~~~~~~~~~~~ + +First read, Note [Dynamic linking on macOS] to understand why on darwin we never +use `-XLinker -rpath`. + +The specification of `Opt_RPath` is as follows: + +The default case `-fuse-rpaths`: +* On darwin, never use `-Xlinker -rpath -Xlinker`, always inject the rpath + afterwards, see `runInjectRPaths`. There is no way to use `-Xlinker` on darwin + as things stand but it wasn't documented in the user guide before this patch how + `-fuse-rpaths` should behave and the fact it was always disabled on darwin. +* Otherwise, use `-Xlinker -rpath -Xlinker` to set the rpath of the executable, + this is the normal way you should set the rpath. + +The case of `-fno-use-rpaths` +* Never inject anything into the rpath. + +When this was first implemented, `Opt_RPath` was disabled on darwin, but +the rpath was still always augmented by `runInjectRPaths`, and there was no way to +stop this. This was problematic because you couldn't build an executable in CI +with a clean rpath. + +-} + -- ----------------------------------------------------------------------------- -- RTS hooks |