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1This patch is based on https://github.com/sternenseemann/cabal/tree/sterni-cabal-3.16-for-aarch64-darwin and has been created using
2git diff 77afa40961a686d36717604864b4c48ed5233bea eeed4f92625bbe2dbfb57f51d953e3b9a495d884 --patch --src-prefix=a/libraries/Cabal/ --dst-prefix=b/libraries/Cabal/
3
4Reasoning and explanation of the patch can be found in the comment in the diff for PathsModule.hs below.
5
6diff --git a/libraries/Cabal/Cabal/src/Distribution/Simple/Build/PathsModule.hs b/libraries/Cabal/Cabal/src/Distribution/Simple/Build/PathsModule.hs
7index 9392acf3c..3417e613a 100644
8--- a/libraries/Cabal/Cabal/src/Distribution/Simple/Build/PathsModule.hs
9+++ b/libraries/Cabal/Cabal/src/Distribution/Simple/Build/PathsModule.hs
10@@ -52,6 +52,7 @@ generatePathsModule pkg_descr lbi clbi =
11 , Z.zIsI386 = buildArch == I386
12 , Z.zIsX8664 = buildArch == X86_64
13 , Z.zIsAArch64 = buildArch == AArch64
14+ , Z.zOr = (||)
15 , Z.zNot = not
16 , Z.zManglePkgName = showPkgName
17 , Z.zPrefix = show flat_prefix
18@@ -61,8 +62,110 @@ generatePathsModule pkg_descr lbi clbi =
19 , Z.zDatadir = zDatadir
20 , Z.zLibexecdir = zLibexecdir
21 , Z.zSysconfdir = zSysconfdir
22+ , -- Sadly we can't be cleverer about this – we can't have literals in the template
23+ Z.zShouldEmitDataDir = shouldEmit "DataDir"
24+ , Z.zShouldEmitLibDir = shouldEmit "LibDir"
25+ , Z.zShouldEmitDynLibDir = shouldEmit "DynLibDir"
26+ , Z.zShouldEmitLibexecDir = shouldEmit "LibexecDir"
27+ , Z.zShouldEmitSysconfDir = shouldEmit "SysconfDir"
28+ , Z.zWarning = zWarning
29+ , Z.zShouldEmitWarning = zShouldEmitWarning
30 }
31 where
32+ -- GHC's NCG backend for aarch64-darwin does not support link-time dead code
33+ -- elimination to the extent that NCG does for other targets. Consequently,
34+ -- we struggle with unnecessarily retained store path references due to the
35+ -- use of `Paths_*` modules – even if `getLibDir` is not used, it'll end up
36+ -- in the final library or executables we build.
37+ --
38+ -- When using a different output for the executables and library, this
39+ -- becomes more sinister: The library will contain a reference to the bin
40+ -- output and itself due to `getLibDir` and `getBinDir`, but the executables
41+ -- will do so, too. Either due to linking dynamically or because the library
42+ -- is linked statically into the executable and retains those references.
43+ -- Since Nix disallows cyclical references between two outputs, it becomes
44+ -- impossible to use the `Paths_*` module and a separate `bin` output for
45+ -- aarch64-darwin.
46+ --
47+ -- The solution we have resorted to for now, is to trim the `Paths_*` module
48+ -- dynamically depending on what references *could* be used without causing
49+ -- a cyclical reference. That has the effect that any code that would not
50+ -- cause a cyclical reference with dead code elimination will compile and
51+ -- work for aarch64-darwin. If the code would use a `get*Dir` function that
52+ -- has been omitted, this would indicate that the code would have caused a
53+ -- cyclical reference anyways.
54+ --
55+ -- The logic for this makes some pretty big assumptions about installation
56+ -- prefixes that probably only hold fully in nixpkgs with
57+ -- `haskellPackages.mkDerivation`. Simple uses outside nixpkgs that have
58+ -- everything below the same prefix should continue to work as expected,
59+ -- though.
60+ --
61+ -- We assume the following:
62+ --
63+ -- - flat_prefix is `$out`.
64+ -- - flat_libdir etc. are always below `$out`.
65+ --
66+ -- Since in the normal case due to static linking `$bin` and `$out` will
67+ -- have the same references in libraries/executables, we need to either
68+ -- prevent usage of `getBinDir` or `getLibDir` to break the cycle in case
69+ -- `flat_bindir` is not below `$out`. We have decided to always allow usage
70+ -- of `getBinDir`, so `getLibDir` gets dropped if a separate `bin` output is
71+ -- used. This has the simple reason that `$out` which contains `flat_libdir`
72+ -- tends to be quite big – we would like to have a `bin` output that doesn't
73+ -- require keeping that around.
74+ pathEmittable :: FilePath -> Bool
75+ pathEmittable p
76+ -- If the executable installation target is below `$out` the reference
77+ -- cycle is within a single output (since libs are installed to `$out`)
78+ -- and thus unproblematic. We can use any and all `get*Dir` functions.
79+ | flat_prefix `isPrefixOf` flat_bindir = True
80+ -- Otherwise, we need to disallow all `get*Dir` functions that would cause
81+ -- a reference to `$out` which contains the libraries that would in turn
82+ -- reference `$bin`. This always include `flat_libdir` and friends, but
83+ -- can also include `flat_datadir` if no separate output for data files is
84+ -- used.
85+ | otherwise = not (flat_prefix `isPrefixOf` p)
86+
87+ -- This list maps the "name" of the directory to whether we want to include
88+ -- it in the `Paths_*` module or not. `shouldEmit` performs a lookup in this.
89+ dirs :: [(String, Bool)]
90+ dirs =
91+ map
92+ (\(name, path) -> (name, pathEmittable path))
93+ [ ("LibDir", flat_libdir)
94+ , ("DynLibDir", flat_dynlibdir)
95+ , ("DataDir", flat_datadir)
96+ , ("LibexecDir", flat_libexecdir)
97+ , ("SysconfDir", flat_sysconfdir)
98+ ]
99+
100+ shouldEmit :: String -> Bool
101+ shouldEmit name =
102+ case lookup name dirs of
103+ Just b -> b
104+ Nothing -> error "panic! BUG in Cabal Paths_ patch for aarch64-darwin, report this at https://github.com/nixos/nixpkgs/issues"
105+
106+ -- This is a comma separated list of all functions that have been omitted.
107+ -- This is included in a GHC warning which will be attached to the `Paths_*`
108+ -- module in case we are dropping any `get*Dir` functions that would
109+ -- normally exist.
110+ --
111+ -- TODO: getDataFileName is not accounted for at the moment.
112+ omittedFunctions :: String
113+ omittedFunctions =
114+ intercalate ", " $
115+ map (("get" ++) . fst) $
116+ filter (not . snd) dirs
117+
118+ zWarning :: String
119+ zWarning =
120+ show $
121+ "The following functions have been omitted by a nixpkgs-specific patch to Cabal: "
122+ ++ omittedFunctions
123+ zShouldEmitWarning :: Bool
124+ zShouldEmitWarning = any (not . snd) dirs
125+
126 supports_cpp = supports_language_pragma
127 supports_rebindable_syntax = ghc_newer_than (mkVersion [7, 0, 1])
128 supports_language_pragma = ghc_newer_than (mkVersion [6, 6, 1])
129diff --git a/libraries/Cabal/Cabal/src/Distribution/Simple/Build/PathsModule/Z.hs b/libraries/Cabal/Cabal/src/Distribution/Simple/Build/PathsModule/Z.hs
130index 8f33717bb..b89775893 100644
131--- a/libraries/Cabal/Cabal/src/Distribution/Simple/Build/PathsModule/Z.hs
132+++ b/libraries/Cabal/Cabal/src/Distribution/Simple/Build/PathsModule/Z.hs
133@@ -20,6 +20,14 @@ data Z
134 zDatadir :: FilePath,
135 zLibexecdir :: FilePath,
136 zSysconfdir :: FilePath,
137+ zShouldEmitLibDir :: Bool,
138+ zShouldEmitDynLibDir :: Bool,
139+ zShouldEmitLibexecDir :: Bool,
140+ zShouldEmitDataDir :: Bool,
141+ zShouldEmitSysconfDir :: Bool,
142+ zShouldEmitWarning :: Bool,
143+ zWarning :: String,
144+ zOr :: (Bool -> Bool -> Bool),
145 zNot :: (Bool -> Bool),
146 zManglePkgName :: (PackageName -> String)}
147 deriving Generic
148@@ -74,10 +82,51 @@ render z_root = execWriter $ do
149 tell "\n"
150 tell "module Paths_"
151 tell (zManglePkgName z_root (zPackageName z_root))
152- tell " (\n"
153+ tell "\n"
154+ tell " "
155+ if (zShouldEmitWarning z_root)
156+ then do
157+ tell "{-# WARNING "
158+ tell (zWarning z_root)
159+ tell " #-}"
160+ return ()
161+ else do
162+ return ()
163+ tell "\n"
164+ tell " (\n"
165 tell " version,\n"
166- tell " getBinDir, getLibDir, getDynLibDir, getDataDir, getLibexecDir,\n"
167- tell " getDataFileName, getSysconfDir\n"
168+ tell " getBinDir,\n"
169+ if (zOr z_root (zNot z_root (zAbsolute z_root)) (zShouldEmitLibDir z_root))
170+ then do
171+ tell " getLibDir,\n"
172+ return ()
173+ else do
174+ return ()
175+ if (zOr z_root (zNot z_root (zAbsolute z_root)) (zShouldEmitDynLibDir z_root))
176+ then do
177+ tell " getDynLibDir,\n"
178+ return ()
179+ else do
180+ return ()
181+ if (zOr z_root (zNot z_root (zAbsolute z_root)) (zShouldEmitLibexecDir z_root))
182+ then do
183+ tell " getLibexecDir,\n"
184+ return ()
185+ else do
186+ return ()
187+ if (zOr z_root (zNot z_root (zAbsolute z_root)) (zShouldEmitDataDir z_root))
188+ then do
189+ tell " getDataFileName,\n"
190+ tell " getDataDir,\n"
191+ return ()
192+ else do
193+ return ()
194+ if (zOr z_root (zNot z_root (zAbsolute z_root)) (zShouldEmitSysconfDir z_root))
195+ then do
196+ tell " getSysconfDir\n"
197+ return ()
198+ else do
199+ return ()
200 tell " ) where\n"
201 tell "\n"
202 if (zNot z_root (zAbsolute z_root))
203@@ -126,57 +175,19 @@ render z_root = execWriter $ do
204 tell (zVersionDigits z_root)
205 tell " []\n"
206 tell "\n"
207- tell "-- |If the argument is a filename, the result is the name of a corresponding\n"
208- tell "-- file on the system on which the program is running, if the file were listed\n"
209- tell "-- in the @data-files@ field of the package's Cabal package description file.\n"
210- tell "-- No check is performed that the given filename is listed in that field.\n"
211- tell "getDataFileName :: FilePath -> IO FilePath\n"
212- tell "getDataFileName name = do\n"
213- tell " dir <- getDataDir\n"
214- tell " return (dir `joinFileName` name)\n"
215- tell "\n"
216- tell "-- |The location of the directory specified by Cabal's @--bindir@ option (where\n"
217- tell "-- executables that the user might invoke are installed). This can be overridden\n"
218- tell "-- at runtime using the environment variable "
219- tell (zManglePkgName z_root (zPackageName z_root))
220- tell "_bindir.\n"
221- tell "getBinDir :: IO FilePath\n"
222- tell "\n"
223- tell "-- |The location of the directory specified by Cabal's @--libdir@ option (where\n"
224- tell "-- object libraries are installed). This can be overridden at runtime using the\n"
225- tell "-- environment variable "
226- tell (zManglePkgName z_root (zPackageName z_root))
227- tell "_libdir.\n"
228- tell "getLibDir :: IO FilePath\n"
229- tell "\n"
230- tell "-- |The location of the directory specified by Cabal's @--dynlibdir@ option\n"
231- tell "-- (where dynamic libraries are installed). This can be overridden at runtime\n"
232- tell "-- using the environment variable "
233- tell (zManglePkgName z_root (zPackageName z_root))
234- tell "_dynlibdir.\n"
235- tell "getDynLibDir :: IO FilePath\n"
236- tell "\n"
237- tell "-- |The location of the directory specified by Cabal's @--datadir@ option (where\n"
238- tell "-- architecture-independent data files are installed). This can be overridden at\n"
239- tell "-- runtime using the environment variable "
240- tell (zManglePkgName z_root (zPackageName z_root))
241- tell "_datadir.\n"
242- tell "getDataDir :: IO FilePath\n"
243- tell "\n"
244- tell "-- |The location of the directory specified by Cabal's @--libexedir@ option\n"
245- tell "-- (where executables that are not expected to be invoked directly by the user\n"
246- tell "-- are installed). This can be overridden at runtime using the environment\n"
247- tell "-- variable "
248- tell (zManglePkgName z_root (zPackageName z_root))
249- tell "_libexedir.\n"
250- tell "getLibexecDir :: IO FilePath\n"
251- tell "\n"
252- tell "-- |The location of the directory specified by Cabal's @--sysconfdir@ option\n"
253- tell "-- (where configuration files are installed). This can be overridden at runtime\n"
254- tell "-- using the environment variable "
255- tell (zManglePkgName z_root (zPackageName z_root))
256- tell "_sysconfdir.\n"
257- tell "getSysconfDir :: IO FilePath\n"
258+ if (zOr z_root (zNot z_root (zAbsolute z_root)) (zShouldEmitDataDir z_root))
259+ then do
260+ tell "-- |If the argument is a filename, the result is the name of a corresponding\n"
261+ tell "-- file on the system on which the program is running, if the file were listed\n"
262+ tell "-- in the @data-files@ field of the package's Cabal package description file.\n"
263+ tell "-- No check is performed that the given filename is listed in that field.\n"
264+ tell "getDataFileName :: FilePath -> IO FilePath\n"
265+ tell "getDataFileName name = do\n"
266+ tell " dir <- getDataDir\n"
267+ tell " return (dir `joinFileName` name)\n"
268+ return ()
269+ else do
270+ return ()
271 tell "\n"
272 let
273 z_var0_function_defs = do
274@@ -204,6 +215,7 @@ render z_root = execWriter $ do
275 tell "\n"
276 if (zRelocatable z_root)
277 then do
278+ tell "\n"
279 tell "\n"
280 tell "getPrefixDirReloc :: FilePath -> IO FilePath\n"
281 tell "getPrefixDirReloc dirRel = do\n"
282@@ -213,31 +225,68 @@ render z_root = execWriter $ do
283 tell (zBindir z_root)
284 tell ") `joinFileName` dirRel)\n"
285 tell "\n"
286+ tell "-- |The location of the directory specified by Cabal's @--bindir@ option (where\n"
287+ tell "-- executables that the user might invoke are installed). This can be overridden\n"
288+ tell "-- at runtime using the environment variable "
289+ tell (zManglePkgName z_root (zPackageName z_root))
290+ tell "_bindir.\n"
291+ tell "getBinDir :: IO FilePath\n"
292 tell "getBinDir = catchIO (getEnv \""
293 tell (zManglePkgName z_root (zPackageName z_root))
294 tell "_bindir\") (\\_ -> getPrefixDirReloc $ "
295 tell (zBindir z_root)
296 tell ")\n"
297+ tell "-- |The location of the directory specified by Cabal's @--libdir@ option (where\n"
298+ tell "-- object libraries are installed). This can be overridden at runtime using the\n"
299+ tell "-- environment variable "
300+ tell (zManglePkgName z_root (zPackageName z_root))
301+ tell "_libdir.\n"
302+ tell "getLibDir :: IO FilePath\n"
303 tell "getLibDir = catchIO (getEnv \""
304 tell (zManglePkgName z_root (zPackageName z_root))
305 tell "_libdir\") (\\_ -> getPrefixDirReloc $ "
306 tell (zLibdir z_root)
307 tell ")\n"
308+ tell "-- |The location of the directory specified by Cabal's @--dynlibdir@ option\n"
309+ tell "-- (where dynamic libraries are installed). This can be overridden at runtime\n"
310+ tell "-- using the environment variable "
311+ tell (zManglePkgName z_root (zPackageName z_root))
312+ tell "_dynlibdir.\n"
313+ tell "getDynLibDir :: IO FilePath\n"
314 tell "getDynLibDir = catchIO (getEnv \""
315 tell (zManglePkgName z_root (zPackageName z_root))
316 tell "_dynlibdir\") (\\_ -> getPrefixDirReloc $ "
317 tell (zDynlibdir z_root)
318 tell ")\n"
319+ tell "-- |The location of the directory specified by Cabal's @--datadir@ option (where\n"
320+ tell "-- architecture-independent data files are installed). This can be overridden at\n"
321+ tell "-- runtime using the environment variable "
322+ tell (zManglePkgName z_root (zPackageName z_root))
323+ tell "_datadir.\n"
324+ tell "getDataDir :: IO FilePath\n"
325 tell "getDataDir = catchIO (getEnv \""
326 tell (zManglePkgName z_root (zPackageName z_root))
327 tell "_datadir\") (\\_ -> getPrefixDirReloc $ "
328 tell (zDatadir z_root)
329 tell ")\n"
330+ tell "-- |The location of the directory specified by Cabal's @--libexedir@ option\n"
331+ tell "-- (where executables that are not expected to be invoked directly by the user\n"
332+ tell "-- are installed). This can be overridden at runtime using the environment\n"
333+ tell "-- variable "
334+ tell (zManglePkgName z_root (zPackageName z_root))
335+ tell "_libexedir.\n"
336+ tell "getLibexecDir :: IO FilePath\n"
337 tell "getLibexecDir = catchIO (getEnv \""
338 tell (zManglePkgName z_root (zPackageName z_root))
339 tell "_libexecdir\") (\\_ -> getPrefixDirReloc $ "
340 tell (zLibexecdir z_root)
341 tell ")\n"
342+ tell "-- |The location of the directory specified by Cabal's @--sysconfdir@ option\n"
343+ tell "-- (where configuration files are installed). This can be overridden at runtime\n"
344+ tell "-- using the environment variable "
345+ tell (zManglePkgName z_root (zPackageName z_root))
346+ tell "_sysconfdir.\n"
347+ tell "getSysconfDir :: IO FilePath\n"
348 tell "getSysconfDir = catchIO (getEnv \""
349 tell (zManglePkgName z_root (zPackageName z_root))
350 tell "_sysconfdir\") (\\_ -> getPrefixDirReloc $ "
351@@ -251,72 +300,186 @@ render z_root = execWriter $ do
352 if (zAbsolute z_root)
353 then do
354 tell "\n"
355- tell "bindir, libdir, dynlibdir, datadir, libexecdir, sysconfdir :: FilePath\n"
356+ tell "bindir :: FilePath\n"
357 tell "bindir = "
358 tell (zBindir z_root)
359 tell "\n"
360- tell "libdir = "
361- tell (zLibdir z_root)
362 tell "\n"
363- tell "dynlibdir = "
364- tell (zDynlibdir z_root)
365+ tell "-- |The location of the directory specified by Cabal's @--bindir@ option (where\n"
366+ tell "-- executables that the user might invoke are installed). This can be overridden\n"
367+ tell "-- at runtime using the environment variable "
368+ tell (zManglePkgName z_root (zPackageName z_root))
369+ tell "_bindir.\n"
370+ tell "getBinDir :: IO FilePath\n"
371+ tell "getBinDir = catchIO (getEnv \""
372+ tell (zManglePkgName z_root (zPackageName z_root))
373+ tell "_bindir\") (\\_ -> return bindir)\n"
374 tell "\n"
375- tell "datadir = "
376- tell (zDatadir z_root)
377+ if (zShouldEmitLibDir z_root)
378+ then do
379+ tell "libdir :: FilePath\n"
380+ tell "libdir = "
381+ tell (zLibdir z_root)
382+ tell "\n"
383+ tell "\n"
384+ tell "-- |The location of the directory specified by Cabal's @--libdir@ option (where\n"
385+ tell "-- object libraries are installed). This can be overridden at runtime using the\n"
386+ tell "-- environment variable "
387+ tell (zManglePkgName z_root (zPackageName z_root))
388+ tell "_libdir.\n"
389+ tell "getLibDir :: IO FilePath\n"
390+ tell "getLibDir = catchIO (getEnv \""
391+ tell (zManglePkgName z_root (zPackageName z_root))
392+ tell "_libdir\") (\\_ -> return libdir)\n"
393+ return ()
394+ else do
395+ return ()
396 tell "\n"
397- tell "libexecdir = "
398- tell (zLibexecdir z_root)
399+ if (zShouldEmitDynLibDir z_root)
400+ then do
401+ tell "dynlibdir :: FilePath\n"
402+ tell "dynlibdir = "
403+ tell (zDynlibdir z_root)
404+ tell "\n"
405+ tell "-- |The location of the directory specified by Cabal's @--dynlibdir@ option\n"
406+ tell "-- (where dynamic libraries are installed). This can be overridden at runtime\n"
407+ tell "-- using the environment variable "
408+ tell (zManglePkgName z_root (zPackageName z_root))
409+ tell "_dynlibdir.\n"
410+ tell "getDynLibDir :: IO FilePath\n"
411+ tell "getDynLibDir = catchIO (getEnv \""
412+ tell (zManglePkgName z_root (zPackageName z_root))
413+ tell "_dynlibdir\") (\\_ -> return dynlibdir)\n"
414+ return ()
415+ else do
416+ return ()
417 tell "\n"
418- tell "sysconfdir = "
419- tell (zSysconfdir z_root)
420+ if (zShouldEmitDataDir z_root)
421+ then do
422+ tell "datadir :: FilePath\n"
423+ tell "datadir = "
424+ tell (zDatadir z_root)
425+ tell "\n"
426+ tell "\n"
427+ tell "-- |The location of the directory specified by Cabal's @--datadir@ option (where\n"
428+ tell "-- architecture-independent data files are installed). This can be overridden at\n"
429+ tell "-- runtime using the environment variable "
430+ tell (zManglePkgName z_root (zPackageName z_root))
431+ tell "_datadir.\n"
432+ tell "getDataDir :: IO FilePath\n"
433+ tell "getDataDir = catchIO (getEnv \""
434+ tell (zManglePkgName z_root (zPackageName z_root))
435+ tell "_datadir\") (\\_ -> return datadir)\n"
436+ return ()
437+ else do
438+ return ()
439 tell "\n"
440+ if (zShouldEmitLibexecDir z_root)
441+ then do
442+ tell "libexecdir :: FilePath\n"
443+ tell "libexecdir = "
444+ tell (zLibexecdir z_root)
445+ tell "\n"
446+ tell "\n"
447+ tell "-- |The location of the directory specified by Cabal's @--libexedir@ option\n"
448+ tell "-- (where executables that are not expected to be invoked directly by the user\n"
449+ tell "-- are installed). This can be overridden at runtime using the environment\n"
450+ tell "-- variable "
451+ tell (zManglePkgName z_root (zPackageName z_root))
452+ tell "_libexedir.\n"
453+ tell "getLibexecDir :: IO FilePath\n"
454+ tell "getLibexecDir = catchIO (getEnv \""
455+ tell (zManglePkgName z_root (zPackageName z_root))
456+ tell "_libexecdir\") (\\_ -> return libexecdir)\n"
457+ return ()
458+ else do
459+ return ()
460 tell "\n"
461- tell "getBinDir = catchIO (getEnv \""
462- tell (zManglePkgName z_root (zPackageName z_root))
463- tell "_bindir\") (\\_ -> return bindir)\n"
464- tell "getLibDir = catchIO (getEnv \""
465- tell (zManglePkgName z_root (zPackageName z_root))
466- tell "_libdir\") (\\_ -> return libdir)\n"
467- tell "getDynLibDir = catchIO (getEnv \""
468- tell (zManglePkgName z_root (zPackageName z_root))
469- tell "_dynlibdir\") (\\_ -> return dynlibdir)\n"
470- tell "getDataDir = catchIO (getEnv \""
471- tell (zManglePkgName z_root (zPackageName z_root))
472- tell "_datadir\") (\\_ -> return datadir)\n"
473- tell "getLibexecDir = catchIO (getEnv \""
474- tell (zManglePkgName z_root (zPackageName z_root))
475- tell "_libexecdir\") (\\_ -> return libexecdir)\n"
476- tell "getSysconfDir = catchIO (getEnv \""
477- tell (zManglePkgName z_root (zPackageName z_root))
478- tell "_sysconfdir\") (\\_ -> return sysconfdir)\n"
479+ if (zShouldEmitSysconfDir z_root)
480+ then do
481+ tell "sysconfdir :: FilePath\n"
482+ tell "sysconfdir = "
483+ tell (zSysconfdir z_root)
484+ tell "\n"
485+ tell "\n"
486+ tell "-- |The location of the directory specified by Cabal's @--sysconfdir@ option\n"
487+ tell "-- (where configuration files are installed). This can be overridden at runtime\n"
488+ tell "-- using the environment variable "
489+ tell (zManglePkgName z_root (zPackageName z_root))
490+ tell "_sysconfdir.\n"
491+ tell "getSysconfDir :: IO FilePath\n"
492+ tell "getSysconfDir = catchIO (getEnv \""
493+ tell (zManglePkgName z_root (zPackageName z_root))
494+ tell "_sysconfdir\") (\\_ -> return sysconfdir)\n"
495+ return ()
496+ else do
497+ return ()
498 tell "\n"
499 return ()
500 else do
501 if (zIsWindows z_root)
502 then do
503+ tell "\n"
504 tell "\n"
505 tell "prefix :: FilePath\n"
506 tell "prefix = "
507 tell (zPrefix z_root)
508 tell "\n"
509 tell "\n"
510+ tell "-- |The location of the directory specified by Cabal's @--bindir@ option (where\n"
511+ tell "-- executables that the user might invoke are installed). This can be overridden\n"
512+ tell "-- at runtime using the environment variable "
513+ tell (zManglePkgName z_root (zPackageName z_root))
514+ tell "_bindir.\n"
515+ tell "getBinDir :: IO FilePath\n"
516 tell "getBinDir = getPrefixDirRel $ "
517 tell (zBindir z_root)
518 tell "\n"
519+ tell "-- |The location of the directory specified by Cabal's @--libdir@ option (where\n"
520+ tell "-- object libraries are installed). This can be overridden at runtime using the\n"
521+ tell "-- environment variable "
522+ tell (zManglePkgName z_root (zPackageName z_root))
523+ tell "_libdir.\n"
524+ tell "getLibDir :: IO FilePath\n"
525 tell "getLibDir = "
526 tell (zLibdir z_root)
527 tell "\n"
528+ tell "-- |The location of the directory specified by Cabal's @--dynlibdir@ option\n"
529+ tell "-- (where dynamic libraries are installed). This can be overridden at runtime\n"
530+ tell "-- using the environment variable "
531+ tell (zManglePkgName z_root (zPackageName z_root))
532+ tell "_dynlibdir.\n"
533+ tell "getDynLibDir :: IO FilePath\n"
534 tell "getDynLibDir = "
535 tell (zDynlibdir z_root)
536 tell "\n"
537+ tell "-- |The location of the directory specified by Cabal's @--datadir@ option (where\n"
538+ tell "-- architecture-independent data files are installed). This can be overridden at\n"
539+ tell "-- runtime using the environment variable "
540+ tell (zManglePkgName z_root (zPackageName z_root))
541+ tell "_datadir.\n"
542+ tell "getDataDir :: IO FilePath\n"
543 tell "getDataDir = catchIO (getEnv \""
544 tell (zManglePkgName z_root (zPackageName z_root))
545 tell "_datadir\") (\\_ -> "
546 tell (zDatadir z_root)
547 tell ")\n"
548+ tell "-- |The location of the directory specified by Cabal's @--libexedir@ option\n"
549+ tell "-- (where executables that are not expected to be invoked directly by the user\n"
550+ tell "-- are installed). This can be overridden at runtime using the environment\n"
551+ tell "-- variable "
552+ tell (zManglePkgName z_root (zPackageName z_root))
553+ tell "_libexedir.\n"
554+ tell "getLibexecDir :: IO FilePath\n"
555 tell "getLibexecDir = "
556 tell (zLibexecdir z_root)
557 tell "\n"
558+ tell "-- |The location of the directory specified by Cabal's @--sysconfdir@ option\n"
559+ tell "-- (where configuration files are installed). This can be overridden at runtime\n"
560+ tell "-- using the environment variable "
561+ tell (zManglePkgName z_root (zPackageName z_root))
562+ tell "_sysconfdir.\n"
563+ tell "getSysconfDir :: IO FilePath\n"
564 tell "getSysconfDir = "
565 tell (zSysconfdir z_root)
566 tell "\n"
567diff --git a/libraries/Cabal/cabal-dev-scripts/src/GenPathsModule.hs b/libraries/Cabal/cabal-dev-scripts/src/GenPathsModule.hs
568index 7c5c947a5..3b7a67498 100644
569--- a/libraries/Cabal/cabal-dev-scripts/src/GenPathsModule.hs
570+++ b/libraries/Cabal/cabal-dev-scripts/src/GenPathsModule.hs
571@@ -42,6 +42,16 @@ $(capture "decls" [d|
572 , zLibexecdir :: FilePath
573 , zSysconfdir :: FilePath
574
575+ , zShouldEmitLibDir :: Bool
576+ , zShouldEmitDynLibDir :: Bool
577+ , zShouldEmitLibexecDir :: Bool
578+ , zShouldEmitDataDir :: Bool
579+ , zShouldEmitSysconfDir :: Bool
580+
581+ , zShouldEmitWarning :: Bool
582+ , zWarning :: String
583+
584+ , zOr :: Bool -> Bool -> Bool
585 , zNot :: Bool -> Bool
586 , zManglePkgName :: PackageName -> String
587 }
588diff --git a/libraries/Cabal/templates/Paths_pkg.template.hs b/libraries/Cabal/templates/Paths_pkg.template.hs
589index a9b02b0ef..d99252a29 100644
590--- a/libraries/Cabal/templates/Paths_pkg.template.hs
591+++ b/libraries/Cabal/templates/Paths_pkg.template.hs
592@@ -31,10 +31,31 @@ For further information about Cabal's options for its configuration step, and
593 their default values, see the Cabal User Guide.
594 -}
595
596-module Paths_{{ manglePkgName packageName }} (
597+module Paths_{{ manglePkgName packageName }}
598+ {% if shouldEmitWarning %}{-# WARNING {{ warning }} #-}{% endif %}
599+ (
600 version,
601- getBinDir, getLibDir, getDynLibDir, getDataDir, getLibexecDir,
602- getDataFileName, getSysconfDir
603+ getBinDir,
604+{# We only care about the absolute case for our emit logic, since only in this
605+ case references are incurred. We are not going to hit isWindows and relocatable
606+ has no absolute references to begin with.
607+#}
608+{% if or (not absolute) shouldEmitLibDir %}
609+ getLibDir,
610+{% endif %}
611+{% if or (not absolute) shouldEmitDynLibDir %}
612+ getDynLibDir,
613+{% endif %}
614+{% if or (not absolute) shouldEmitLibexecDir %}
615+ getLibexecDir,
616+{% endif %}
617+{% if or (not absolute) shouldEmitDataDir %}
618+ getDataFileName,
619+ getDataDir,
620+{% endif %}
621+{% if or (not absolute) shouldEmitSysconfDir %}
622+ getSysconfDir
623+{% endif %}
624 ) where
625
626 {% if not absolute %}
627@@ -73,6 +94,7 @@ catchIO = Exception.catch
628 version :: Version
629 version = Version {{ versionDigits }} []
630
631+{% if or (not absolute) shouldEmitDataDir %}
632 -- |If the argument is a filename, the result is the name of a corresponding
633 -- file on the system on which the program is running, if the file were listed
634 -- in the @data-files@ field of the package's Cabal package description file.
635@@ -81,37 +103,7 @@ getDataFileName :: FilePath -> IO FilePath
636 getDataFileName name = do
637 dir <- getDataDir
638 return (dir `joinFileName` name)
639-
640--- |The location of the directory specified by Cabal's @--bindir@ option (where
641--- executables that the user might invoke are installed). This can be overridden
642--- at runtime using the environment variable {{ manglePkgName packageName }}_bindir.
643-getBinDir :: IO FilePath
644-
645--- |The location of the directory specified by Cabal's @--libdir@ option (where
646--- object libraries are installed). This can be overridden at runtime using the
647--- environment variable {{ manglePkgName packageName }}_libdir.
648-getLibDir :: IO FilePath
649-
650--- |The location of the directory specified by Cabal's @--dynlibdir@ option
651--- (where dynamic libraries are installed). This can be overridden at runtime
652--- using the environment variable {{ manglePkgName packageName }}_dynlibdir.
653-getDynLibDir :: IO FilePath
654-
655--- |The location of the directory specified by Cabal's @--datadir@ option (where
656--- architecture-independent data files are installed). This can be overridden at
657--- runtime using the environment variable {{ manglePkgName packageName }}_datadir.
658-getDataDir :: IO FilePath
659-
660--- |The location of the directory specified by Cabal's @--libexedir@ option
661--- (where executables that are not expected to be invoked directly by the user
662--- are installed). This can be overridden at runtime using the environment
663--- variable {{ manglePkgName packageName }}_libexedir.
664-getLibexecDir :: IO FilePath
665-
666--- |The location of the directory specified by Cabal's @--sysconfdir@ option
667--- (where configuration files are installed). This can be overridden at runtime
668--- using the environment variable {{ manglePkgName packageName }}_sysconfdir.
669-getSysconfDir :: IO FilePath
670+{% endif %}
671
672 {% defblock function_defs %}
673 minusFileName :: FilePath -> String -> FilePath
674@@ -140,48 +132,155 @@ splitFileName p = (reverse (path2++drive), reverse fname)
675
676 {% if relocatable %}
677
678+{# Relocatable can not incur any absolute references, so we can ignore it.
679+ Additionally, --enable-relocatable is virtually useless in Nix builds
680+#}
681+
682 getPrefixDirReloc :: FilePath -> IO FilePath
683 getPrefixDirReloc dirRel = do
684 exePath <- getExecutablePath
685 let (dir,_) = splitFileName exePath
686 return ((dir `minusFileName` {{ bindir }}) `joinFileName` dirRel)
687
688+-- |The location of the directory specified by Cabal's @--bindir@ option (where
689+-- executables that the user might invoke are installed). This can be overridden
690+-- at runtime using the environment variable {{ manglePkgName packageName }}_bindir.
691+getBinDir :: IO FilePath
692 getBinDir = catchIO (getEnv "{{ manglePkgName packageName }}_bindir") (\_ -> getPrefixDirReloc $ {{ bindir }})
693+-- |The location of the directory specified by Cabal's @--libdir@ option (where
694+-- object libraries are installed). This can be overridden at runtime using the
695+-- environment variable {{ manglePkgName packageName }}_libdir.
696+getLibDir :: IO FilePath
697 getLibDir = catchIO (getEnv "{{ manglePkgName packageName }}_libdir") (\_ -> getPrefixDirReloc $ {{ libdir }})
698+-- |The location of the directory specified by Cabal's @--dynlibdir@ option
699+-- (where dynamic libraries are installed). This can be overridden at runtime
700+-- using the environment variable {{ manglePkgName packageName }}_dynlibdir.
701+getDynLibDir :: IO FilePath
702 getDynLibDir = catchIO (getEnv "{{ manglePkgName packageName }}_dynlibdir") (\_ -> getPrefixDirReloc $ {{ dynlibdir }})
703+-- |The location of the directory specified by Cabal's @--datadir@ option (where
704+-- architecture-independent data files are installed). This can be overridden at
705+-- runtime using the environment variable {{ manglePkgName packageName }}_datadir.
706+getDataDir :: IO FilePath
707 getDataDir = catchIO (getEnv "{{ manglePkgName packageName }}_datadir") (\_ -> getPrefixDirReloc $ {{ datadir }})
708+-- |The location of the directory specified by Cabal's @--libexedir@ option
709+-- (where executables that are not expected to be invoked directly by the user
710+-- are installed). This can be overridden at runtime using the environment
711+-- variable {{ manglePkgName packageName }}_libexedir.
712+getLibexecDir :: IO FilePath
713 getLibexecDir = catchIO (getEnv "{{ manglePkgName packageName }}_libexecdir") (\_ -> getPrefixDirReloc $ {{ libexecdir }})
714+-- |The location of the directory specified by Cabal's @--sysconfdir@ option
715+-- (where configuration files are installed). This can be overridden at runtime
716+-- using the environment variable {{ manglePkgName packageName }}_sysconfdir.
717+getSysconfDir :: IO FilePath
718 getSysconfDir = catchIO (getEnv "{{ manglePkgName packageName }}_sysconfdir") (\_ -> getPrefixDirReloc $ {{ sysconfdir }})
719
720 {% useblock function_defs %}
721
722 {% elif absolute %}
723
724-bindir, libdir, dynlibdir, datadir, libexecdir, sysconfdir :: FilePath
725+bindir :: FilePath
726 bindir = {{ bindir }}
727-libdir = {{ libdir }}
728-dynlibdir = {{ dynlibdir }}
729-datadir = {{ datadir }}
730-libexecdir = {{ libexecdir }}
731-sysconfdir = {{ sysconfdir }}
732
733+-- |The location of the directory specified by Cabal's @--bindir@ option (where
734+-- executables that the user might invoke are installed). This can be overridden
735+-- at runtime using the environment variable {{ manglePkgName packageName }}_bindir.
736+getBinDir :: IO FilePath
737 getBinDir = catchIO (getEnv "{{ manglePkgName packageName }}_bindir") (\_ -> return bindir)
738+
739+{% if shouldEmitLibDir %}
740+libdir :: FilePath
741+libdir = {{ libdir }}
742+
743+-- |The location of the directory specified by Cabal's @--libdir@ option (where
744+-- object libraries are installed). This can be overridden at runtime using the
745+-- environment variable {{ manglePkgName packageName }}_libdir.
746+getLibDir :: IO FilePath
747 getLibDir = catchIO (getEnv "{{ manglePkgName packageName }}_libdir") (\_ -> return libdir)
748+{% endif %}
749+
750+{% if shouldEmitDynLibDir %}
751+dynlibdir :: FilePath
752+dynlibdir = {{ dynlibdir }}
753+-- |The location of the directory specified by Cabal's @--dynlibdir@ option
754+-- (where dynamic libraries are installed). This can be overridden at runtime
755+-- using the environment variable {{ manglePkgName packageName }}_dynlibdir.
756+getDynLibDir :: IO FilePath
757 getDynLibDir = catchIO (getEnv "{{ manglePkgName packageName }}_dynlibdir") (\_ -> return dynlibdir)
758+{% endif %}
759+
760+{% if shouldEmitDataDir %}
761+datadir :: FilePath
762+datadir = {{ datadir }}
763+
764+-- |The location of the directory specified by Cabal's @--datadir@ option (where
765+-- architecture-independent data files are installed). This can be overridden at
766+-- runtime using the environment variable {{ manglePkgName packageName }}_datadir.
767+getDataDir :: IO FilePath
768 getDataDir = catchIO (getEnv "{{ manglePkgName packageName }}_datadir") (\_ -> return datadir)
769+{% endif %}
770+
771+{% if shouldEmitLibexecDir %}
772+libexecdir :: FilePath
773+libexecdir = {{ libexecdir }}
774+
775+-- |The location of the directory specified by Cabal's @--libexedir@ option
776+-- (where executables that are not expected to be invoked directly by the user
777+-- are installed). This can be overridden at runtime using the environment
778+-- variable {{ manglePkgName packageName }}_libexedir.
779+getLibexecDir :: IO FilePath
780 getLibexecDir = catchIO (getEnv "{{ manglePkgName packageName }}_libexecdir") (\_ -> return libexecdir)
781+{% endif %}
782+
783+{% if shouldEmitSysconfDir %}
784+sysconfdir :: FilePath
785+sysconfdir = {{ sysconfdir }}
786+
787+-- |The location of the directory specified by Cabal's @--sysconfdir@ option
788+-- (where configuration files are installed). This can be overridden at runtime
789+-- using the environment variable {{ manglePkgName packageName }}_sysconfdir.
790+getSysconfDir :: IO FilePath
791 getSysconfDir = catchIO (getEnv "{{ manglePkgName packageName }}_sysconfdir") (\_ -> return sysconfdir)
792+{% endif %}
793
794 {% elif isWindows %}
795
796+{# We are only trying to fix the problem for aarch64-darwin with this patch,
797+ so let's ignore Windows which we can reach via pkgsCross, for example.
798+#}
799+
800 prefix :: FilePath
801 prefix = {{ prefix }}
802
803+-- |The location of the directory specified by Cabal's @--bindir@ option (where
804+-- executables that the user might invoke are installed). This can be overridden
805+-- at runtime using the environment variable {{ manglePkgName packageName }}_bindir.
806+getBinDir :: IO FilePath
807 getBinDir = getPrefixDirRel $ {{ bindir }}
808+-- |The location of the directory specified by Cabal's @--libdir@ option (where
809+-- object libraries are installed). This can be overridden at runtime using the
810+-- environment variable {{ manglePkgName packageName }}_libdir.
811+getLibDir :: IO FilePath
812 getLibDir = {{ libdir }}
813+-- |The location of the directory specified by Cabal's @--dynlibdir@ option
814+-- (where dynamic libraries are installed). This can be overridden at runtime
815+-- using the environment variable {{ manglePkgName packageName }}_dynlibdir.
816+getDynLibDir :: IO FilePath
817 getDynLibDir = {{ dynlibdir }}
818+-- |The location of the directory specified by Cabal's @--datadir@ option (where
819+-- architecture-independent data files are installed). This can be overridden at
820+-- runtime using the environment variable {{ manglePkgName packageName }}_datadir.
821+getDataDir :: IO FilePath
822 getDataDir = catchIO (getEnv "{{ manglePkgName packageName }}_datadir") (\_ -> {{ datadir }})
823+-- |The location of the directory specified by Cabal's @--libexedir@ option
824+-- (where executables that are not expected to be invoked directly by the user
825+-- are installed). This can be overridden at runtime using the environment
826+-- variable {{ manglePkgName packageName }}_libexedir.
827+getLibexecDir :: IO FilePath
828 getLibexecDir = {{ libexecdir }}
829+-- |The location of the directory specified by Cabal's @--sysconfdir@ option
830+-- (where configuration files are installed). This can be overridden at runtime
831+-- using the environment variable {{ manglePkgName packageName }}_sysconfdir.
832+getSysconfDir :: IO FilePath
833 getSysconfDir = {{ sysconfdir }}
834
835 getPrefixDirRel :: FilePath -> IO FilePath