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GHC 9.10.3 · lts/ghc-9.10.x · c74966e · 2026-09-27

ModuleCabal-3.12.1.0Haskell2010

Distribution.Simple.Configure

This deals with the configure phase. It provides the configure action which is given the package description and configure flags. It then tries to: configure the compiler; resolves any conditionals in the package description; resolve the package dependencies; check if all the extensions used by this package are supported by the compiler; check that all the build tools are available (including version checks if appropriate); checks for any required pkg-config packages (updating the BuildInfo with the results)

Then based on all this it saves the info in the LocalBuildInfo and writes it out to the dist/setup-config file. It also displays various details to the user, the amount of information displayed depending on the verbosity level.

  • 1 type
  • 25 values
  • PackageCabal-3.12.1.0
  • Exports26
  • LanguageHaskell2010
  • LicenceBSD-3-Clause
  • SourceConfigure.hs
valuefindDistPref
  1. :: FilePath

    default "dist" prefix

  2. -> Flag FilePath

    override "dist" prefix

  3. -> IO FilePath
#

Return the "dist/" prefix, or the default prefix. The prefix is taken from (in order of highest to lowest preference) the override prefix, the "CABAL_BUILDDIR" environment variable, or the default prefix.

valuefindDistPrefOrDefault
  1. :: Flag FilePath

    override "dist" prefix

  2. -> IO FilePath
#

Return the "dist/" prefix, or the default prefix. The prefix is taken from (in order of highest to lowest preference) the override prefix, the "CABAL_BUILDDIR" environment variable, or defaultDistPref is used. Call this function to resolve a *DistPref flag whenever it is not known to be set. (The *DistPref flags are always set to a definite value before invoking UserHooks.)

Create a PackageIndex that makes *any libraries that might be* defined internally to this package look like installed packages, in case an executable should refer to any of them as dependencies.

It must be *any libraries that might be* defined rather than the actual definitions, because these depend on conditionals in the .cabal file, and we haven't resolved them yet. finalizePD does the resolution of conditionals, and it takes internalPackageSet as part of its input.

In GHC 8.0, the string we pass to GHC to use for symbol names for a package can be an arbitrary, IPID-compatible string. However, prior to GHC 8.0 there are some restrictions on what format this string can be (due to how ghc-pkg parsed the key):

  1. In GHC 7.10, the string had either be of the form foo_ABCD, where foo is a non-semantic alphanumeric/hyphenated prefix and ABCD is two base-64 encoded 64-bit integers, or a GHC 7.8 style identifier.

  2. In GHC 7.8, the string had to be a valid package identifier like foo-0.1.

So, the problem is that Cabal, in general, has a general IPID, but needs to figure out a package key / package ID that the old ghc-pkg will actually accept. But there's an EVERY WORSE problem: if ghc-pkg decides to parse an identifier foo-0.1-xxx as if it were a package identifier, which means it will SILENTLY DROP the "xxx" (because it's a tag, and Cabal does not allow tags.) So we must CONNIVE to ensure that we don't pick something that looks like this.

So this function attempts to define a mapping into the old formats.

The mapping for GHC 7.8 and before:

  • We use the *compatibility* package name and version. For public libraries this is just the package identifier; for internal libraries, it's something like "z-pkgname-z-libname-0.1". See computeCompatPackageName for more details.

The mapping for GHC 7.10:

  • For CLibName: If the IPID is of the form foo-0.1-ABCDEF where foo_ABCDEF would validly parse as a package key, we pass ABCDEF. (NB: not all hashes parse this way, because GHC 7.10 mandated that these hashes be two base-62 encoded 64 bit integers), but hashes that Cabal generated using computeComponentId are guaranteed to have this form.

    If it is not of this form, we rehash the IPID into the correct form and pass that.

  • For sub-components, we rehash the IPID into the correct format and pass that.

Compute the effective value of the profiling flags --enable-library-profiling and --enable-executable-profiling from the specified ConfigFlags. This may be useful for external Cabal tools which need to interact with Setup in a backwards-compatible way: the most predictable mechanism for enabling profiling across many legacy versions is to NOT use --enable-profiling and use those two flags instead.

Note that --enable-executable-profiling also affects profiling of benchmarks and (non-detailed) test suites.

valueccLdOptionsBuildInfo :: [String] -> [String] -> [String] -> BuildInfo
#

Makes a BuildInfo from C compiler and linker flags.

This can be used with the output from configuration programs like pkg-config and similar package-specific programs like mysql-config, freealut-config etc. For example:

ccflags <- getDbProgramOutput verbosity prog progdb ["--cflags"]
ldflags <- getDbProgramOutput verbosity prog progdb ["--libs"]
ldflags_static <- getDbProgramOutput verbosity prog progdb ["--libs", "--static"]
return (ccldOptionsBuildInfo (words ccflags) (words ldflags) (words ldflags_static))

The user interface specifies the package dbs to use with a combination of --global, --user and --package-db=global|user|clear|$file. This function combines the global/user flag and interprets the package-db flag into a single package db stack.

datadata ConfigStateFileError
#

The errors that can be thrown when reading the setup-config file.

Instances2Show, Exception