GitLab

Cheng Shao pushed to branch wip/fix-unreg at Glasgow Haskell Compiler / GHC

Commits:

cab3cfbc

by Cheng Shao at 2026-06-26T16:23:18+00:00

hadrian/rts: fix unregisterised build for gcc 15+

This patch fixes unregisterised build for gcc 15+:

- Pass -optc-Wno-error in hadrian when +werror enables -optc-Werror,
  see added comment for details.
- For RTS functions that the codegen would emit calls, ensure their
  real prototype is hidden when the header is included in .hc fies
  (IN_STG_CODE), and the dummy prototype is provided to match the EFF_
  convention.

In the future we should get rid of EFF_ (#14647) and remove these
hacks, but for now this patch makes unregisterised work again on newer
toolchains. Fixes #27404.

Co-authored-by: Codex <codex@openai.com>

4 changed files:

+ changelog.d/fix-unreg
hadrian/src/Flavour.hs
rts/include/rts/NonMoving.h
rts/include/stg/MiscClosures.h

Changes:

changelog.d/fix-unreg

 +section: packaging
 +synopsis: Fix unregisterised build for gcc 15+
 +issues: #27404
 +mrs: !16264

hadrian/src/Flavour.hs

@@ -35,7 +35,9 @@ import Data.Either
  import Data.Map (Map)
  import qualified Data.Map as M
  import qualified Data.Set as Set
 +import GHC.Toolchain.Target
  import Oracles.Flag
 +import Oracles.Setting
  import Packages
  import Flavour.Type
  import Settings.Parser
@@ -140,8 +142,9 @@ addArgs args' fl = fl { extraArgs = extraArgs fl <> args' }
  -- in unix and/or hsc2hs to make cross-compiling unix completely free
  -- from warnings.
  werror :: Flavour -> Flavour
 -werror =
 -  addArgs $ mconcat
 +werror = addArgs $ do
 +  stage <- getStage
 +  mconcat
      [ builder Ghc
          ? notStage0
          ? mconcat
@@ -159,6 +162,15 @@ werror =
            , arg "-optc-Wno-error=unknown-pragmas"
              -- rejected inlinings are highly dependent upon toolchain and way
            , arg "-optc-Wno-error=inline"
 +            -- when building unregisterised, gcc 15+ complains "error:
 +            -- function called through a non-compatible type" with
 +            -- -Werror (#27404). no corresponding -Wno-foo for it so
 +            -- -Wno-error is needed.
 +            --
 +            -- TODO: get rid of EFF_ altogether (#14647) and make sure
 +            -- unregisterised backend emits clean C without needing
 +            -- these hacks.
 +          , queryTargetTarget stage tgtUnregisterised ? arg "-optc-Wno-error"
+           ]
        -- N.B. We currently don't build the boot libraries' C sources with -Werror
        -- as this tends to be a portability nightmare.

rts/include/rts/NonMoving.h

@@ -18,6 +18,14 @@ struct StgClosure_;
  struct StgThunk_;
  struct Capability_;
 +#if IN_STG_CODE
++
 +EFF_(updateRemembSetPushClosure_);
++
 +EFF_(updateRemembSetPushThunk_);
++
 +#else
++
  /* This is called by the code generator */
  extern
  void updateRemembSetPushClosure_(StgRegTable *reg, struct StgClosure_ *p);
@@ -25,6 +33,8 @@ void updateRemembSetPushClosure_(StgRegTable *reg, struct StgClosure_ *p);
  extern
  void updateRemembSetPushThunk_(StgRegTable *reg, struct StgThunk_ *p);
 +#endif
++
  // Forward declaration for unregisterised backend.
  EF_(stg_copyArray_barrier);

rts/include/stg/MiscClosures.h

@@ -617,7 +617,11 @@ extern StgWord      CCS_SYSTEM[];
  //    'GHC.StgToCmm.Prof'
  // as opposed to real prototype declared in
  //    'rts/include/rts/prof/CCS.h'
 +#if IN_STG_CODE
 +EFF_(enterFunCCS);
 +#else
  void enterFunCCS (void *reg, void *ccsfn);
 +#endif
  void * pushCostCentre (void *ccs, void *cc);
  // Capability.c