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50188615
by Ian Duncan at 2026-05-14T13:45:07+02:00
AArch64: use ASR not LSR for MO_U_Shr at W8/W16
The unsigned right shift (MO_U_Shr) for sub-word widths (W8, W16)
with a variable shift amount was emitting ASR (arithmetic/signed shift
right) after zero-extending with UXTB/UXTH. This should be LSR
(logical/unsigned shift right). After zero-extension the upper bits
happen to be 0 so ASR produces the same result, but it is semantically
wrong and would break if the zero-extension were ever optimized away.
Includes assembly output test (grep for lsr) and runtime test
verifying unsigned right shift of Word8 and Word16 values.
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28666fbf
by Vladislav Zavialov at 2026-05-19T12:44:05-04:00
Add type families: Tuple, Constraints, Tuple#, Sum# (#27179)
These type families map tuples of types to the corresponding Tuple<N>,
Tuple<N>#, CTuple<N>, and Sum<N># types. Some examples at N=2:
Tuple (Int, Bool) = Tuple2 Int Bool
Constraints (Show a, Eq a) = CTuple2 (Show a) (Eq a)
Tuple# (Int#, Float#) = Tuple2# Int# Float#
Sum# (Int#, Float#) = Sum2# Int# Float#
See GHC Proposal #145 "Non-punning list and tuple syntax".
To make the Sum# instance at N=64 possible, this patch also introduces
the Sum64# constructor declaration and bumps mAX_SUM_SIZE from 63 to 64.
Metric Increase:
ghc_experimental_dir
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41c2448b
by Wen Kokke at 2026-05-19T12:44:53-04:00
rts: Add IPE event class for -l
This commit adds a new IPE event class to the -l RTS flag.
Previously, IPE events were enabled unconditionally.
However, the IPE events can easily grow to hundreds or thousands of megabytes.
With the new event class you can pass, e.g., -l-I to disable IPE events.
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62536551
by Wen Kokke at 2026-05-19T12:44:53-04:00
ghc-internal: Add TraceFlags.traceIPE
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e45312d1
by Wen Kokke at 2026-05-19T12:44:53-04:00
testsuite: Add test for TraceFlags.traceIpe
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4768d9aa
by Wen Kokke at 2026-05-19T12:44:53-04:00
ghc-internal: Add DebugFlags.ipe
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bc1b5c69
by Wen Kokke at 2026-05-19T12:44:53-04:00
testsuite: Add test for DebugFlags.ipe
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0da1543f
by Duncan Coutts at 2026-05-19T12:45:37-04:00
Document removal of the signal-based interval timer
Update mentions within the RTS section of the users guide.
Add a changelog entry.
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b2911514
by Duncan Coutts at 2026-05-19T12:45:37-04:00
Fix section for an recent changelog entry
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d6d76a7a
by David Eichmann at 2026-05-19T12:46:19-04:00
ghc-toolchain: implement llvm program versioning logic
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2dd36fa3
by Wolfgang Jeltsch at 2026-05-20T04:49:52-04:00
Turn `Trustworthy` into `Safe` in `base` where possible
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f4399dd1
by Wolfgang Jeltsch at 2026-05-20T04:50:37-04:00
Make the current `base` buildable with GHC 10.0
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1a7de232
by Duncan Coutts at 2026-05-20T12:26:25-04:00
Hadrian: remove legacy rts .so symlinks
For compatibility with the old makefile based build system, hadrian had
rules to generate symlinks from unversioned to versioned names for the
rts .so/.dynlib file, like libHSrts-ghcx.y.so -> libHSrts-1.0.3-ghcx.y.so
We no longer need these symlinks since the makefile build system has
been retired some time ago. The need for these symlinks is awkward on
windows where we cannot (in practice) create symlinks. So rather than
make them conditional (non-windows), just remove them entirely.
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286f1adf
by fendor at 2026-05-20T12:27:09-04:00
Fix regression T27202: `:load` and `:add` work in GHCi
To fix the regression there are conceptually two major things that we
fix:
* We don't remove the `importDirs` from `interactive-session`
* When `:add`ing a module, we don't try to find them via PackageImports
* The PackageImport is wrong as we can't know the package-name at
this stage in ghc/UI.hs
What does it mean to not remove the `importDirs` from
`interactive-session`?
It means that, given some initial `DynFlags`, we will use those
`importDirs` in `interactive-session`.
The initial `DynFlags`, however, depend on how you initialise the GHC
session.
For a simple session, initialised by
ghc -isrc -this-unit-id main
It is simple, just use the `DynFlags` given on the cli.
Thus, `main` and `interactive-session` will have the same `DynFlags`,
except for the `homeUnitId` and `interactive-session` depends on `main`
by construction of the GHCi session.
What about a multiple home unit session, though?
ghc -unit @unit1 -unit @unit2
What are the `DynFlags` in this cli invocation? It shouldn't be either
`@unti1` nor `@unit2`, as the order shouldn't matter or any other
implicit condition.
For consistency, we decide that the initial `DynFlags` are the top
`DynFlags` on the cli, ignoring `-unit` flags.
Thus, in this example, there are no `importsDirs` regardless of what we
might find in `@unit1` and `@unit2`.
But in this invocation:
ghc -isrc -unit @unit1 -unit @unit2
The `interactive-session` will have the `importsDirs` `src`.
Note, `-isrc` will be inherited in `@unit1` and `@unit2`, so you need to
explicitly use `-i` to clear the `importsDirs`, in order to avoid
accidentally adding `src` as an import directory to all other home
units.
This fix has been made possible by the improvements introduced in
!15888, which avoids ambiguity when a home unit shares the `importsDirs`
with the `interactive-session`, on top of being much faster for multiple
home units.
Adds regression tests for T27202 for `:load`ing and `:add`ing modules
that are located in import directories.
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728662de
by fendor at 2026-05-20T12:27:09-04:00
Use home unit package db stacks in GHCi prompt and session unit
In order to import modules from home unit dependencies (e.g., `Data.Map`),
the ghci prompt unit needs to populate its `UnitState`.
This is tricky to handle correctly, which `PackageDBFlag`s should we use
to populate the `UnitState`?
We decide, the most intuitive solution for users is to depend on all
`PackageDBFlag`s, so that any dependency can be imported in GHCi.
This assumes consistency in the `PackageDBFlag`s, so no two home units
specify `PackageDBFlag`s that are inconsistent with each other.
We could simply concat all the `PackageDBFlag`s of the existing home
units, but later `PackageDBFlag`s shadow earlier ones, leading to the
last processed home units' `PackageDBFlag`s to shadow the earlier ones.
This is hard to fix, we need to give users the capability to provide ghc
options for the ghci prompt home unit.
However, as this is considerably more work, we decided on an
approximation that should work out most of the time.
Package Db stacks in cabal and stack follow a certain structure:
-no-user-package-db > -package-db $cabal-store > -package-db $local-db
The first two arguments are always the same, namely the
`-no-user-package-db` and `-package-db`.
We compute the longest common prefix over all home units, and use that
as the start of the package db stack. Then, over the rest of the
`PackageDBFlag`s, we simply take the union and append them to our
initial stack.
We assume, that the rest of package dbs only defines very few, "local"
units that are usually not shadowing each other.
This allows us to get a relatively consistent package database stack for
the ghci prompt home unit.
Similar reasoning applies to the session unit in order to add modules to
the session and have dependencies available in the module.
We do something similar for `-package` flags, to make sure only the
correct units are actually visible in the ghci session.
This time, we simply take the union of all `PackageFlag`s, allowing us
to import modules from the home unit dependencies.
In the future, it would be beneficial to allow the user to provide the
exact ghc options to control the visibilities. For now, this will have
to do.
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c1dec14d
by Alan Zimmerman at 2026-05-20T20:16:10+01:00
EPA: Fix span for qualified multiline string
Fix the span for a qualified multiline string like
Text."""
I'm a multiline
Text value
!
"""
to extend to the end of the entire string, not just the first line.
Closes #27274