SYNOPSIS

ghc [option|filename]...
ghci [option|filename]...

DESCRIPTION

This manual page documents briefly the ghc and ghci commands. Note that ghci is not yet available on all architectures. Extensive documentation is available in various other formats including DVI, PostScript and HTML; see below.

Each of GHC's command line options is classified as either static or dynamic. A static flag may only be specified on the command line, whereas a dynamic flag may also be given in an OPTIONS pragma in a source file or set from the GHCi command-line with :set.

As a rule of thumb, all the language options are dynamic, as are the warning options and the debugging options.

The rest are static, with the notable exceptions of -v, -cpp, -fasm, -fvia-C, -fllvm, and " -#include . The OPTIONS sections lists the status of each flag.

Common suffixes of file names for Haskell are:

.hs

Haskell source code; preprocess, compile

.lhs

literate Haskell source; unlit, preprocess, compile

.hi

Interface file; contains information about exported symbols

.hc

intermediate C files

.x_o

way x object files; common ways are: p, u, s

.x_hi

way x interface files

OPTIONS

Verbosity options

-v -vn -fprint-explicit-foralls -fprint-explicit-kinds -ferror-spans -Hsize -Rghc-timing

Alternative modes of operation

--help,-? --interactive --make -e expr --show-iface -M --supported-extensions, --supported-languages --show-options --info --version, -V --numeric-version --print-libdir

Which phases to run

-E -C -S -c -x suffix

Redirecting output

-hcsuf suffix -hidir dir -hisuf suffix -o filename -odir dir -ohi filename -osuf suffix -stubdir dir -dumpdir dir -outputdir dir

Keeping intermediate files

-keep-hc-file or
              -keep-hc-files  -keep-llvm-file or
              -keep-llvm-files  -keep-s-file or
              -keep-s-files  -keep-tmp-files  

Temporary files

-tmpdir

Finding imports

-idir1:dir2:... -i

Interface file options

-ddump-hi -ddump-hi-diffs -ddump-minimal-imports --show-iface file

Recompilation checking

-fforce-recomp -fno-force-recomp

Interactive-mode options

-ignore-dot-ghci -ghci-script -fbreak-on-error -fno-break-on-error -fbreak-on-exception -fno-break-on-exception -fghci-hist-size=n (default is 50) -fprint-evld-with-show -fno-print-evld-with-show -fprint-bind-result -fno-print-bind-result -fno-print-bind-contents -fno-implicit-import-qualified -interactive-print

Packages

-this-package-key P -package P -hide-all-packages -hide-package name -ignore-package name -package-db file -clear-package-db -no-global-package-db -global-package-db -no-user-package-db -user-package-db -no-auto-link-packages -trust P -distrust P -distrust-all

Language options

-fcontext-stack=n -fglasgow-exts -fno-glasgow-exts -firrefutable-tuples -fno-irrefutable-tuples -fpackage-trust -ftype-function-depth=n -XAllowAmbiguousTypes -XNoAllowAmbiguousTypes -XArrows -XNoArrows -XAutoDeriveTypeable -XNoAutoDeriveTypeable -XBangPatterns -XNoBangPatterns -XBinaryLiterals -XNoBinaryLiterals -XCApiFFI -XNoCAPIFFI -XConstrainedClassMethods -XNoConstrainedClassMethods -XConstraintKinds -XNoConstraintKinds -XCPP -XNoCPP -XDataKinds -XNoDataKinds -XDefaultSignatures -XNoDefaultSignatures -XDeriveAnyClass -XNoDeriveAnyClass -XDeriveDataTypeable -XNoDeriveDataTypeable -XDeriveFunctor -XNoDeriveFunctor -XDeriveFoldable -XNoDeriveFoldable -XDeriveGeneric -XNoDeriveGeneric -XDeriveTraversable -XNoDeriveTraversable -XDisambiguateRecordFields -XNoDisambiguateRecordFields -XEmptyCase -XNoEmptyCase -XEmptyDataDecls -XNoEmptyDataDecls -XExistentialQuantification -XNoExistentialQuantification -XExplicitForAll -XNoExplicitForAll -XExplicitNamespaces -XNoExplicitNamespaces -XExtendedDefaultRules -XNoExtendedDefaultRules -XFlexibleContexts -XNoFlexibleContexts -XFlexibleInstances -XNoFlexibleInstances -XForeignFunctionInterface -XNoForeignFunctionInterface -XFunctionalDependencies -XNoFunctionalDependencies -XGADTs -XNoGADTs -XGADTSyntax -XNoGADTSyntax -XGeneralizedNewtypeDeriving -XNoGeneralizedNewtypeDeriving -XGenerics -XNoGenerics -XImplicitParams -XNoImplicitParams -XNoImplicitPrelude -XImplicitPrelude -XImpredicativeTypes -XNoImpredicativeTypes -XIncoherentInstances -XNoIncoherentInstances -XInstanceSigs -XNoInstanceSigs -XInterruptibleFFI -XNoInterruptibleFFI -XKindSignatures -XNoKindSignatures -XLambdaCase -XNoLambdaCase -XLiberalTypeSynonyms -XNoLiberalTypeSynonyms -XMagicHash -XNoMagicHash -XMonadComprehensions -XNoMonadComprehensions -XMonoLocalBinds -XNoMonoLocalBinds -XNoMonomorphismRestriction -XMonomorphismRestriction -XMultiParamTypeClasses -XNoMultiParamTypeClasses -XMultiWayIf -XNoMultiWayIf -XNamedFieldPuns -XNoNamedFieldPuns -XNamedWildCards -XNoNamedWildCards -XNegativeLiterals -XNoNegativeLiterals -XNoNPlusKPatterns -XNPlusKPatterns -XNullaryTypeClasses -XNoNullaryTypeClasses -XNumDecimals -XNoNumDecimals -XOverlappingInstances -XNoOverlappingInstances -XOverloadedLists -XNoOverloadedLists -XOverloadedStrings -XNoOverloadedStrings -XPackageImports -XNoPackageImports -XParallelArrays -XNoParallelArrays -XParallelListComp -XNoParallelListComp -XPartialTypeSignatures -XNoPartialTypeSignatures -XPatternGuards -XNoPatternGuards -XPatternSynonyms -XNoPatternSynonyms -XPolyKinds -XNoPolyKinds -XPolymorphicComponents -XNoPolymorphicComponents -XPostfixOperators -XNoPostfixOperators -XQuasiQuotes -XNoQuasiQuotes -XRank2Types -XNoRank2Types -XRankNTypes -XNoRankNTypes -XRebindableSyntax -XNoRebindableSyntax -XRecordWildCards -XNoRecordWildCards -XRecursiveDo -XNoRecursiveDo -XRelaxedPolyRec -XNoRelaxedPolyRec -XRoleAnnotations -XNoRoleAnnotations -XSafe -XScopedTypeVariables -XNoScopedTypeVariables -XStandaloneDeriving -XNoStandaloneDeriving -XTemplateHaskell -XNoTemplateHaskell -XNoTraditionalRecordSyntax -XTraditionalRecordSyntax -XTransformListComp -XNoTransformListComp -XTrustworthy -XTupleSections -XNoTupleSections -XTypeFamilies -XNoTypeFamilies -XTypeOperators -XNoTypeOperators -XTypeSynonymInstances -XNoTypeSynonymInstances -XUnboxedTuples -XNoUnboxedTuples -XUndecidableInstances -XNoUndecidableInstances -XUnicodeSyntax -XNoUnicodeSyntax -XUnliftedFFITypes -XNoUnliftedFFITypes -XUnsafe -XViewPatterns -XNoViewPatterns

Warnings

-W -w -w -Wall -w -Werror -Wwarn -fdefer-type-errors -fno-defer-type-errors -fdefer-typed-holes -fno-defer-typed-holes -fhelpful-errors -fno-helpful-errors -fwarn-deprecated-flags -fno-warn-deprecated-flags -fwarn-duplicate-constraints -fno-warn-duplicate-constraints -fwarn-duplicate-exports -fno-warn-duplicate-exports -fwarn-hi-shadowing -fno-warn-hi-shadowing -fwarn-identities -fno-warn-identities -fwarn-implicit-prelude -fno-warn-implicit-prelude -fwarn-incomplete-patterns -fno-warn-incomplete-patterns -fwarn-incomplete-uni-patterns -fno-warn-incomplete-uni-patterns -fwarn-incomplete-record-updates -fno-warn-incomplete-record-updates -fwarn-lazy-unlifted-bindings -fno-warn-lazy-unlifted-bindings -fwarn-missing-fields -fno-warn-missing-fields -fwarn-missing-import-lists -fnowarn-missing-import-lists -fwarn-missing-methods -fno-warn-missing-methods -fwarn-missing-signatures -fno-warn-missing-signatures -fwarn-missing-exported-sigs -fno-warn-missing-exported-sigs -fwarn-missing-local-sigs -fno-warn-missing-local-sigs -fwarn-monomorphism-restriction -fno-warn-monomorphism-restriction -fwarn-name-shadowing -fno-warn-name-shadowing -fwarn-orphans, -fwarn-auto-orphans -fno-warn-orphans, -fno-warn-auto-orphans -fwarn-overlapping-patterns -fno-warn-overlapping-patterns -fwarn-tabs -fno-warn-tabs -fwarn-type-defaults -fno-warn-type-defaults -fwarn-unrecognised-pragmas -fno-warn-unrecognised-pragmas -fwarn-unticked-promoted-constructors -fno-warn-unticked-promoted-constructors -fwarn-unused-binds -fno-warn-unused-binds -fwarn-unused-imports -fno-warn-unused-imports -fwarn-unused-matches -fno-warn-unused-matches -fwarn-unused-do-bind -fno-warn-unused-do-bind -fwarn-wrong-do-bind -fno-warn-wrong-do-bind -fwarn-unsafe -fno-warn-unsafe -fwarn-safe -fno-warn-safe -fwarn-trustworthy-safe -fno-warn-safe -fwarn-warnings-deprecations -fno-warn-warnings-deprecations -fwarn-amp -fno-warn-amp -fwarn-typed-holes -fno-warn-typed-holes -fwarn-partial-type-signatures -fno-warn-partial-type-signatures -fwarn-deriving-typeable -fno-warn-deriving-typeable

Optimisation levels

-O0 -O -O or -O1 -O0 -O2 -O0 -Odph

Individual optimisations

-fcall-arity -fno-call-arity -fcase-merge -fno-case-merge -fcmm-elim-common-blocks -fno-cmm-elim-common-blocks -fcmm-sink -fno-cmm-sink -fcpr-off -fcse -fno-cse -fdicts-cheap -fno-dicts-cheap -fdicts-strict -fno-dicts-strict -fdmd-tx-dict-sel
             -fno-dmd-tx-dict-sel  -fdo-eta-reduction -fno-do-eta-reduction  -fdo-lambda-eta-expansion -fno-do-lambda-eta-expansion  -feager-blackholing  -fenable-rewrite-rules -fno-enable-rewrite-rules  -fexcess-precision -fno-excess-precision  -fexpose-all-unfoldings -fno-expose-all-unfoldings  -ffloat-in -fno-float-in  -ffull-laziness -fno-full-laziness  -ffun-to-thunk -fno-fun-to-thunk  -fignore-asserts -fno-ignore-asserts  -fignore-interface-pragmas -fno-ignore-interface-pragmas  -flate-dmd-anal -fno-late-dmd-anal  -fliberate-case   -fliberate-case-threshold=n -fno-liberate-case-threshold  -floopification -fno-loopification  -fmax-inline-alloc-size=n  
            -fmax-inline-memcpy-insns=n
              
            -fmax-inline-memset-insns=n
              -fmax-relevant-binds=n -fno-max-relevant-bindings  -fmax-simplifier-iterations=n  -fmax-worker-args=n  -fno-opt-coercion  -fno-pre-inlining  -fno-state-hack  -fomit-interface-pragmas -fno-omit-interface-pragmas  -fomit-yields -fno-omit-yields  -fpedantic-bottoms -fno-pedantic-bottoms  -fregs-graph -fno-regs-graph  -fregs-iterative -fno-regs-iterative  -fsimplifier-phases=n  -fsimpl-tick-factor=n  -fspec-constr -fno-spec-constr  -fspec-constr-count=n -fno-spec-constr-count  -fspec-constr-threshold=n -fno-spec-constr-threshold  -fspecialise -fno-specialise  -fstatic-argument-transformation -fno-static-argument-transformation  -fstrictness -fno-strictness  -fstrictness-before=n  -funbox-small-strict-fields -fno-unbox-small-strict-fields  -funbox-strict-fields -fno-unbox-strict-fields  -funfolding-creation-threshold=n  -funfolding-dict-discount=n  -funfolding-fun-discount=n  -funfolding-keeness-factor=n  -funfolding-use-threshold=n  -fvectorisation-avoidance -fno-vectorisation-avoidance  -fvectorise -fno-vectorise  

Profiling options

-prof -fprof-auto -fno-prof-auto -fprof-auto-top -fno-prof-auto -fprof-auto-exported -fno-prof-auto -fprof-cafs -fno-prof-cafs -fno-prof-count-entries -fprof-count-entries -ticky

Program coverage options

-fhpc -hpcdir dir

Haskell pre-processor options

-F

C pre-processor options

-cpp -Dsymbol=value -U -Usymbol -Idir

Code generation options

-fasm -fllvm -fno-code -fwrite-interface -fbyte-code -fobject-code

Linking options

-shared -staticlib -fPIC -dynamic -dynamic-too -dyno -dynosuf -dynload -framework name -framework-path name -llib -Ldir -main-is --mk-dll -no-hs-main -rtsopts, -rtsopts={none,some,all} -with-rtsopts=opts -no-link -split-objs -static -threaded -debug -ticky -eventlog -fno-gen-manifest -fno-embed-manifest -fno-shared-implib -dylib-install-name path -rdynamic

Plugin options

-fplugin=module -fplugin-opt=module:args

Replacing phases

-pgmL cmd -pgmP cmd -pgmc cmd -pgmlo cmd -pgmlc cmd -pgms cmd -pgma cmd -pgml cmd -pgmdll cmd -pgmF cmd -pgmwindres cmd -pgmlibtool cmd -pgmreadelf cmd

Forcing options to particular phases

-optL option -optP option -optF option -optc option -optlo option -optlc option -opta option -optl option -optdll option -optwindres option

Platform-specific options

-msse2

Compiler debugging options

-dcore-lint -ddump-to-file -ddump-asm -ddump-bcos -ddump-cmm -ddump-core-stats -ddump-cse -ddump-deriv -ddump-ds -ddump-foreign -ddump-hpc -ddump-inlinings -ddump-llvm -ddump-occur-anal -ddump-opt-cmm -ddump-parsed -ddump-prep -ddump-rn -ddump-rule-firings -ddump-rule-rewrites -ddump-rules -ddump-vect -ddump-simpl -ddump-simpl-iterations -ddump-spec -ddump-splices -ddump-stg -ddump-stranal -ddump-strsigs -ddump-tc -dth-dec-file -ddump-types -ddump-worker-wrapper -ddump-if-trace -ddump-tc-trace -ddump-vt-trace -ddump-rn-trace -ddump-rn-stats -ddump-simpl-stats -dno-debug-output -dppr-debug -dppr-user-length -dppr-colsNNN -dppr-case-as-let -dsuppress-all -dsuppress-uniques -dsuppress-idinfo -dsuppress-module-prefixes -dsuppress-type-signatures -dsuppress-type-applications -dsuppress-coercions -dsource-stats -dcmm-lint -dstg-lint -dstg-stats -dverbose-core2core -dverbose-stg2stg -dshow-passes -dfaststring-stats -frule-check

Misc compiler options

-jN -fno-hi-version-check -fhistory-size -fno-ghci-history -fno-ghci-sandbox

VERBOSITY OPTIONS

-v

verbose mode (equivalent to -v3) [dynamic]

-vn

set verbosity level [dynamic]

-fprint-explicit-foralls

print explicit forall quantification in types [dynamic]

-fprint-explicit-kinds

print explicit kind foralls and kind arguments in types [dynamic]

-ferror-spans

output full span in error messages [dynamic]

-Hsize

Set the minimum heap size to size [dynamic]

-Rghc-timing

Summarise timing stats for GHC (same as +RTS -tstderr) [dynamic]

ALTERNATIVE MODES OF OPERATION

--help,-?

Disply help [mode]

--interactive

Interactive mode - normally used by just running ghci; see for details. [mode]

--make

Build a multi-module Haskell program, automatically figuring out dependencies. Likely to be much easier, and faster, than using make; see for details.. [mode]

-e expr

Evaluate expr; see for details. [mode]

--show-iface

Display the contents of an interface file. [mode]

-M

Generate dependency information suitable for use in a Makefile; see for details. [mode]

--supported-extensions, --supported-languages

display the supported language extensions [mode]

--show-options

display the supported command line options [mode]

--info

display information about the compiler [mode]

--version, -V

display GHC version [mode]

--numeric-version

display GHC version (numeric only) [mode]

--print-libdir

display GHC library directory [mode]

WHICH PHASES TO RUN

-E

Stop after preprocessing (.hspp file) [mode]

-C

Stop after generating C (.hc file) [mode]

-S

Stop after generating assembly (.s file) [mode]

-c

Stop after generating object (.o) file [mode]

-x suffix

Override default behaviour for source files [dynamic]

REDIRECTING OUTPUT

-hcsuf suffix

set the suffix to use for intermediate C files [dynamic]

-hidir dir

set directory for interface files [dynamic]

-hisuf suffix

set the suffix to use for interface files [dynamic]

-o filename

set output filename [dynamic]

-odir dir

set directory for object files [dynamic]

-ohi filename

set the filename in which to put the interface [dynamic]

-osuf suffix

set the output file suffix [dynamic]

-stubdir dir

redirect FFI stub files [dynamic]

-dumpdir dir

redirect dump files [dynamic]

-outputdir dir

set output directory [dynamic]

KEEPING INTERMEDIATE FILES

-keep-hc-file or

              -keep-hc-files  retain intermediate .hc files [dynamic]

-keep-llvm-file or

              -keep-llvm-files  retain intermediate LLVM .ll files [dynamic]

-keep-s-file or

              -keep-s-files  retain intermediate .s files [dynamic]

-keep-tmp-files

retain all intermediate temporary files [dynamic]

TEMPORARY FILES

-tmpdir

set the directory for temporary files [dynamic]

FINDING IMPORTS

-idir1:dir2:...

add dir, dir2, etc. to import path [dynamic/:set]

-i

Empty the import directory list [dynamic/:set]

INTERFACE FILE OPTIONS

-ddump-hi

Dump the new interface to stdout [dynamic]

-ddump-hi-diffs

Show the differences vs. the old interface [dynamic]

-ddump-minimal-imports

Dump a minimal set of imports [dynamic]

--show-iface file

See . []

RECOMPILATION CHECKING

-fforce-recomp

Turn off recompilation checking. This is implied by any -ddump-X option when compiling a single file (i.e. when using -c). [dynamic]

INTERACTIVE-MODE OPTIONS

-ignore-dot-ghci

Disable reading of .ghci files [dynamic]

-ghci-script

Read additional .ghci files [dynamic]

-fbreak-on-error

Break on uncaught exceptions and errors [dynamic]

-fbreak-on-exception

Break on any exception thrown [dynamic]

-fghci-hist-size=n

Set the number of entries GHCi keeps for :history [dynamic]

-fprint-evld-with-show

Enable usage of Show instances in :print [dynamic]

-fprint-bind-result

Turn on printing of binding results in GHCi [dynamic]

-fno-print-bind-contents

Turn off printing of binding contents in GHCi [dynamic]

-fno-implicit-import-qualified

Turn off implicit qualified import of everything in GHCi [dynamic]

-interactive-print

Select the function to use for printing evaluated expressions in GHCi [dynamic]

PACKAGES

-this-package-key P

Compile to be part of package P [dynamic]

-package P

Expose package P [dynamic/:set]

-hide-all-packages

Hide all packages by default [dynamic]

-hide-package name

Hide package P [dynamic/:set]

-ignore-package name

Ignore package P [dynamic/:set]

-package-db file

Add file to the package db stack. [dynamic]

-clear-package-db

Clear the package db stack. [dynamic]

-no-global-package-db

Remove the global package db from the stack. [dynamic]

-global-package-db

Add the global package db to the stack. [dynamic]

-no-user-package-db

Remove the user's package db from the stack. [dynamic]

-user-package-db

Add the user's package db to the stack. [dynamic]

-no-auto-link-packages

Don't automatically link in the base and rts packages. [dynamic]

-trust P

Expose package P and set it to be trusted [dynamic/:set]

-distrust P

Expose package P and set it to be distrusted [dynamic/:set]

-distrust-all

Distrust all packages by default [dynamic/:set]

LANGUAGE OPTIONS

-fcontext-stack=n

set the limit for type-class context reduction. Default is 100. [dynamic]

-fglasgow-exts

Deprecated. Enable most language extensions; see for exactly which ones. [dynamic]

-firrefutable-tuples

Make tuple pattern matching irrefutable [dynamic]

-fpackage-trust

Enable Safe Haskell trusted package requirement for trustworthy modules. [dynamic]

-ftype-function-depth=n

set the limit for type function reductions. Default is 200. [dynamic]

-XAllowAmbiguousTypes

Allow the user to write ambiguous types, and the type inference engine to infer them. [dynamic]

-XArrows

Enable arrow notation extension [dynamic]

-XAutoDeriveTypeable

As of GHC 7.10, this option is not needed, and should not be used. Automatically derive Typeable instances for every datatype and type class declaration. Implies -XDeriveDataTypeable. [dynamic]

-XBangPatterns

Enable bang patterns. [dynamic]

-XBinaryLiterals

Enable support for binary literals. [dynamic]

-XCApiFFI

Enable the CAPI calling convention. [dynamic]

-XConstrainedClassMethods

Enable constrained class methods. [dynamic]

-XConstraintKinds

Enable a kind of constraints. [dynamic]

-XCPP

Enable the C preprocessor. [dynamic]

-XDataKinds

Enable datatype promotion. [dynamic]

-XDefaultSignatures

Enable default signatures. [dynamic]

-XDeriveAnyClass

Enable deriving for any class. [dynamic]

-XDeriveDataTypeable

Enable deriving for the Data class. Implied by -XAutoDeriveTypeable. [dynamic]

-XDeriveFunctor

Enable deriving for the Functor class. Implied by -XDeriveTraversable. [dynamic]

-XDeriveFoldable

Enable deriving for the Foldable class. Implied by -XDeriveTraversable. [dynamic]

-XDeriveGeneric

Enable deriving for the Generic class. [dynamic]

-XDeriveTraversable

Enable deriving for the Traversable class. Implies -XDeriveFunctor and -XDeriveFoldable. [dynamic]

-XDisambiguateRecordFields

Enable record field disambiguation. Implied by -XRecordWildCards. [dynamic]

-XEmptyCase

Allow empty case alternatives. [dynamic]

-XEmptyDataDecls

Enable empty data declarations. [dynamic]

-XExistentialQuantification

Enable existential quantification. [dynamic]

-XExplicitForAll

Enable explicit universal quantification. Implied by -XScopedTypeVariables, -XLiberalTypeSynonyms, -XRankNTypes and -XExistentialQuantification. [dynamic]

-XExplicitNamespaces

Enable using the keyword type to specify the namespace of entries in imports and exports (). Implied by -XTypeOperators and -XTypeFamilies. [dynamic]

-XExtendedDefaultRules

Use GHCi's extended default rules in a normal module. [dynamic]

-XFlexibleContexts

Enable flexible contexts. Implied by -XImplicitParams. [dynamic]

-XFlexibleInstances

Enable flexible instances. Implies -XTypeSynonymInstances. Implied by -XImplicitParams. [dynamic]

-XForeignFunctionInterface

Enable foreign function interface. [dynamic]

-XFunctionalDependencies

Enable functional dependencies. Implies -XMultiParamTypeClasses. [dynamic]

-XGADTs

Enable generalised algebraic data types. Implies -XGADTSyntax and -XMonoLocalBinds. [dynamic]

-XGADTSyntax

Enable generalised algebraic data type syntax. [dynamic]

-XGeneralizedNewtypeDeriving

Enable newtype deriving. [dynamic]

-XGenerics

Deprecated, does nothing. No longer enables generic classes. See also GHC's support for generic programming. [dynamic]

-XImplicitParams

Enable Implicit Parameters. Implies -XFlexibleContexts and -XFlexibleInstances. [dynamic]

-XNoImplicitPrelude

Don't implicitly import Prelude. Implied by -XRebindableSyntax. [dynamic]

-XImpredicativeTypes

Enable impredicative types. Implies -XRankNTypes. [dynamic]

-XIncoherentInstances

Enable incoherent instances. Implies -XOverlappingInstances. [dynamic]

-XInstanceSigs

Enable instance signatures. [dynamic]

-XInterruptibleFFI

Enable interruptible FFI. [dynamic]

-XKindSignatures

Enable kind signatures. Implied by -XTypeFamilies and -XPolyKinds. [dynamic]

-XLambdaCase

Enable lambda-case expressions. [dynamic]

-XLiberalTypeSynonyms

Enable liberalised type synonyms. [dynamic]

-XMagicHash

Allow "#" as a postfix modifier on identifiers. [dynamic]

-XMonadComprehensions

Enable monad comprehensions. [dynamic]

-XMonoLocalBinds

Enable do not generalise local bindings. Implied by -XTypeFamilies and -XGADTs. [dynamic]

-XNoMonomorphismRestriction

Disable the monomorphism restriction. [dynamic]

-XMultiParamTypeClasses

Enable multi parameter type classes. Implied by -XFunctionalDependencies. [dynamic]

-XMultiWayIf

Enable multi-way if-expressions. [dynamic]

-XNamedFieldPuns

Enable record puns. [dynamic]

-XNamedWildCards

Enable named wildcards. [dynamic]

-XNegativeLiterals

Enable support for negative literals. [dynamic]

-XNoNPlusKPatterns

Disable support for n+k patterns. [dynamic]

-XNullaryTypeClasses

Deprecated, does nothing. nullary (no parameter) type classes are now enabled using -XMultiParamTypeClasses. [dynamic]

-XNumDecimals

Enable support for 'fractional' integer literals. [dynamic]

-XOverlappingInstances

Enable overlapping instances. [dynamic]

-XOverloadedLists

Enable overloaded lists. [dynamic]

-XOverloadedStrings

Enable overloaded string literals. [dynamic]

-XPackageImports

Enable package-qualified imports. [dynamic]

-XParallelArrays

Enable parallel arrays. Implies -XParallelListComp. [dynamic]

-XParallelListComp

Enable parallel list comprehensions. Implied by -XParallelArrays. [dynamic]

-XPartialTypeSignatures

Enable partial type signatures. [dynamic]

-XPatternGuards

Enable pattern guards. [dynamic]

-XPatternSynonyms

Enable pattern synonyms. [dynamic]

-XPolyKinds

Enable kind polymorphism. Implies -XKindSignatures. [dynamic]

-XPolymorphicComponents

Enable polymorphic components for data constructors. [dynamic, synonym for -XRankNTypes]

-XPostfixOperators

Enable postfix operators. [dynamic]

-XQuasiQuotes

Enable quasiquotation. [dynamic]

-XRank2Types

Enable rank-2 types. [dynamic, synonym for -XRankNTypes]

-XRankNTypes

Enable rank-N types. Implied by -XImpredicativeTypes. [dynamic]

-XRebindableSyntax

Employ rebindable syntax. Implies -XNoImplicitPrelude. [dynamic]

-XRecordWildCards

Enable record wildcards. Implies -XDisambiguateRecordFields. [dynamic]

-XRecursiveDo

Enable recursive do (mdo) notation. [dynamic]

-XRelaxedPolyRec

(deprecated) Relaxed checking for mutually-recursive polymorphic functions. [dynamic]

-XRoleAnnotations

Enable role annotations. [dynamic]

-XSafe

Enable the Safe Haskell Safe mode. [dynamic]

-XScopedTypeVariables

Enable lexically-scoped type variables. [dynamic]

-XStandaloneDeriving

Enable standalone deriving. [dynamic]

-XTemplateHaskell

Enable Template Haskell. [dynamic]

-XNoTraditionalRecordSyntax

Disable support for traditional record syntax (as supported by Haskell 98) C {f = x} [dynamic]

-XTransformListComp

Enable generalised list comprehensions. [dynamic]

-XTrustworthy

Enable the Safe Haskell Trustworthy mode. [dynamic]

-XTupleSections

Enable tuple sections. [dynamic]

-XTypeFamilies

Enable type families. Implies -XExplicitNamespaces, -XKindSignatures and -XMonoLocalBinds. [dynamic]

-XTypeOperators

Enable type operators. Implies -XExplicitNamespaces. [dynamic]

-XTypeSynonymInstances

Enable type synonyms in instance heads. Implied by -XFlexibleInstances. [dynamic]

-XUnboxedTuples

Enable unboxed tuples. [dynamic]

-XUndecidableInstances

Enable undecidable instances. [dynamic]

-XUnicodeSyntax

Enable unicode syntax. [dynamic]

-XUnliftedFFITypes

Enable unlifted FFI types. [dynamic]

-XUnsafe

Enable Safe Haskell Unsafe mode. [dynamic]

-XViewPatterns

Enable view patterns. [dynamic]

WARNINGS

-W

enable normal warnings [dynamic]

-w

disable all warnings [dynamic]

-Wall

enable almost all warnings (details in ) [dynamic]

-Werror

make warnings fatal [dynamic]

-Wwarn

make warnings non-fatal [dynamic]

-fdefer-type-errors

Turn type errors into warnings, deferring the error until runtime. Implies -fdefer-typed-holes. [dynamic]

-fdefer-typed-holes

Convert typed hole errors into warnings, deferring the error until runtime. Implied by -fdefer-type-errors. See also -fwarn-typed-holes. [dynamic]

-fhelpful-errors

Make suggestions for mis-spelled names. [dynamic]

-fwarn-deprecated-flags

warn about uses of commandline flags that are deprecated [dynamic]

-fwarn-duplicate-constraints

warn when a constraint appears duplicated in a type signature [dynamic]

-fwarn-duplicate-exports

warn when an entity is exported multiple times [dynamic]

-fwarn-hi-shadowing

warn when a .hi file in the current directory shadows a library [dynamic]

-fwarn-identities

warn about uses of Prelude numeric conversions that are probably the identity (and hence could be omitted) [dynamic]

-fwarn-implicit-prelude

warn when the Prelude is implicitly imported [dynamic]

-fwarn-incomplete-patterns

warn when a pattern match could fail [dynamic]

-fwarn-incomplete-uni-patterns

warn when a pattern match in a lambda expression or pattern binding could fail [dynamic]

-fwarn-incomplete-record-updates

warn when a record update could fail [dynamic]

-fwarn-lazy-unlifted-bindings

(deprecated) warn when a pattern binding looks lazy but must be strict [dynamic]

-fwarn-missing-fields

warn when fields of a record are uninitialised [dynamic]

-fwarn-missing-import-lists

warn when an import declaration does not explicitly list all the names brought into scope [dynamic]

-fwarn-missing-methods

warn when class methods are undefined [dynamic]

-fwarn-missing-signatures

warn about top-level functions without signatures [dynamic]

-fwarn-missing-exported-sigs

warn about top-level functions without signatures, only if they are exported. takes precedence over -fwarn-missing-signatures [dynamic]

-fwarn-missing-local-sigs

warn about polymorphic local bindings without signatures [dynamic]

-fwarn-monomorphism-restriction

warn when the Monomorphism Restriction is applied [dynamic]

-fwarn-name-shadowing

warn when names are shadowed [dynamic]

-fwarn-orphans, -fwarn-auto-orphans

warn when the module contains orphan instance declarations or rewrite rules [dynamic]

-fwarn-overlapping-patterns

warn about overlapping patterns [dynamic]

-fwarn-tabs

warn if there are tabs in the source file [dynamic]

-fwarn-type-defaults

warn when defaulting happens [dynamic]

-fwarn-unrecognised-pragmas

warn about uses of pragmas that GHC doesn't recognise [dynamic]

-fwarn-unticked-promoted-constructors

warn if promoted constructors are not ticked [dynamic]

-fwarn-unused-binds

warn about bindings that are unused [dynamic]

-fwarn-unused-imports

warn about unnecessary imports [dynamic]

-fwarn-unused-matches

warn about variables in patterns that aren't used [dynamic]

-fwarn-unused-do-bind

warn about do bindings that appear to throw away values of types other than () [dynamic]

-fwarn-wrong-do-bind

warn about do bindings that appear to throw away monadic values that you should have bound instead [dynamic]

-fwarn-unsafe

warn if the module being compiled is regarded to be unsafe. Should be used to check the safety status of modules when using safe inference. Works on all module types, even those using explicit Safe Haskell modes (such as -XTrustworthy) and so can be used to have the compiler check any assumptions made. [dynamic]

-fwarn-safe

warn if the module being compiled is regarded to be safe. Should be used to check the safety status of modules when using safe inference. Works on all module types, even those using explicit Safe Haskell modes (such as -XTrustworthy) and so can be used to have the compiler check any assumptions made. [dynamic]

-fwarn-trustworthy-safe

warn if the module being compiled is marked as -XTrustworthy but it could instead be marked as -XSafe, a more informative bound. Can be used to detect once a Safe Haskell bound can be improved as dependencies are updated. [dynamic]

-fwarn-warnings-deprecations

warn about uses of functions & types that have warnings or deprecated pragmas [dynamic]

-fwarn-amp

(deprecated) warn on definitions conflicting with the Applicative-Monad Proposal (AMP) [dynamic]

-fwarn-typed-holes

Report warnings when typed hole errors are deferred until runtime. See -fdefer-typed-holes. [dynamic]

-fwarn-partial-type-signatures

warn about holes in partial type signatures when -XPartialTypesignatures is enabled. Not applicable when -XPartialTypesignatures is not enabled, in which case errors are generated for such holes. See . [dynamic]

-fwarn-deriving-typeable

warn when encountering a request to derive an instance of class Typeable. As of GHC 7.10, such declarations are unnecessary and are ignored by the compiler because GHC has a custom solver for discharging this type of constraint. [dynamic]

OPTIMISATION LEVELS

-O0

Disable optimisations (default) [dynamic]

-O or -O1

Enable level 1 optimisations [dynamic]

-O2

Enable level 2 optimisations [dynamic]

-Odph

Enable level 2 optimisations, set -fmax-simplifier-iterations=20 and -fsimplifier-phases=3. [dynamic]

INDIVIDUAL OPTIMISATIONS

-fcall-arity

Enable call-arity optimisation. Implied by -O. [dynamic]

-fcase-merge

Enable case-merging. Implied by -O. [dynamic]

-fcmm-elim-common-blocks

Enable Cmm common block elimination. Implied by -O. [dynamic]

-fcmm-sink

Enable Cmm sinking. Implied by -O. [dynamic]

-fcpr-off

Switch off CPR analysis in the demand analyser. [static]

-fcse

Enable common sub-expression elimination. Implied by -O. [dynamic]

-fdicts-cheap

Make dictionary-valued expressions seem cheap to the optimiser. [dynamic]

-fdicts-strict

Make dictionaries strict [dynamic]

-fdmd-tx-dict-sel

              Use a special demand transformer for dictionary selectors. Always enabled by default. [dynamic]

-fdo-eta-reduction

Enable eta-reduction. Implied by -O. [dynamic]

-fdo-lambda-eta-expansion

Enable lambda eta-expansion. Always enabled by default. [dynamic]

-feager-blackholing

Turn on eager blackholing [dynamic]

-fenable-rewrite-rules

Switch on all rewrite rules (including rules generated by automatic specialisation of overloaded functions). Implied by -O. [dynamic]

-fexcess-precision

Enable excess intermediate precision [dynamic]

-fexpose-all-unfoldings

Expose all unfoldings, even for very large or recursive functions. [dynamic]

-ffloat-in

Turn on the float-in transformation. Implied by -O. [dynamic]

-ffull-laziness

Turn on full laziness (floating bindings outwards). Implied by -O. [dynamic]

-ffun-to-thunk

Allow worker-wrapper to convert a function closure into a thunk if the function does not use any of its arguments. Off by default. [dynamic]

-fignore-asserts

Ignore assertions in the source. Implied by -O. [dynamic]

-fignore-interface-pragmas

Ignore pragmas in interface files. Implied by -O0 only. [dynamic]

-flate-dmd-anal

Run demand analysis again, at the end of the simplification pipeline [dynamic]

-fliberate-case

Turn on the liberate-case transformation. Implied by -O2. [dynamic]

-fliberate-case-threshold=n

Set the size threshold for the liberate-case transformation to n (default: 2000) [dynamis]

-floopification

Turn saturated self-recursive tail-calls into local jumps in the generated assembly. Implied by -O. [dynamic]

-fmax-inline-alloc-size=n

Set the maximum size of inline array allocations to n bytes (default: 128). GHC will allocate non-pinned arrays of statically known size in the current nursery block if they're no bigger than n bytes, ignoring GC overheap. This value should be quite a bit smaller than the block size (typically: 4096). [dynamic]

            -fmax-inline-memcpy-insns=n
              Inline memcpy calls if they would generate no more than n pseudo instructions (default: 32). [dynamic]

            -fmax-inline-memset-insns=n
              Inline memset calls if they would generate no more than n pseudo instructions (default: 32). [dynamic]

-fmax-relevant-binds=n

Set the maximum number of bindings to display in type error messages (default 6). [dynamic]

-fmax-simplifier-iterations=n

Set the max iterations for the simplifier (default 4). [dynamic]

-fmax-worker-args=n

If a worker has that many arguments, none will be unpacked anymore (default: 10) [dynamic]

-fno-opt-coercion

Turn off the coercion optimiser [static]

-fno-pre-inlining

Turn off pre-inlining [dynamic]

-fno-state-hack

Turn off the "state hack" whereby any lambda with a real-world state token as argument is considered to be single-entry. Hence OK to inline things inside it. [static]

-fomit-interface-pragmas

Don't generate interface pragmas. Implied by -O0 only. [dynamic]

-fomit-yields

Omit heap checks when no allocation is being performed. [dynamic]

-fpedantic-bottoms

Make GHC be more precise about its treatment of bottom (but see also -fno-state-hack). In particular, GHC will not eta-expand through a case expression. [dynamic]

-fregs-graph

Use the graph colouring register allocator for register allocation in the native code generator. Implied by -O2. [dynamic]

-fregs-iterative

Use the iterative coalescing graph colouring register allocator in the native code generator. [dynamic]

-fsimplifier-phases=n

Set the number of phases for the simplifier (default 2). Ignored with -O0. [dynamic]

-fsimpl-tick-factor=n

Set the percentage factor for simplifier ticks (default 100) [dynamic]

-fspec-constr

Turn on the SpecConstr transformation. Implied by -O2. [dynamic]

-fspec-constr-count=n

Set to n (default: 3) the maximum number of specialisations that will be created for any one function by the SpecConstr transformation [dynamic]

-fspec-constr-threshold=n

Set the size threshold for the SpecConstr transformation to n (default: 2000) [dynamic]

-fspecialise

Turn on specialisation of overloaded functions. Implied by -O. [dynamic]

-fstatic-argument-transformation

Turn on the static argument transformation. [dynamic]

-fstrictness

Turn on strictness analysis. Implied by -O. [dynamic]

-fstrictness-before=n

Run an additional strictness analysis before simplifier phase n [dynamic]

-funbox-small-strict-fields

Flatten strict constructor fields with a pointer-sized representation. Implied by -O. [dynamic]

-funbox-strict-fields

Flatten strict constructor fields [dynamic]

-funfolding-creation-threshold=n

Tweak unfolding settings. Default: 750 [dynamic]

-funfolding-dict-discount=n

Tweak unfolding settings. Default: 30 [dynamic]

-funfolding-fun-discount=n

Tweak unfolding settings. Default: 60 [dynamic]

-funfolding-keeness-factor=n

Tweak unfolding settings. Default: 1.5 [dynamic]

-funfolding-use-threshold=n

Tweak unfolding settings. Default: 60 [dynamic]

-fvectorisation-avoidance

Enable vectorisation avoidance. Always enabled by default. [dynamic]

-fvectorise

Enable vectorisation of nested data parallelism [dynamic]

PROFILING OPTIONS

-prof

Turn on profiling [dynamic]

-fprof-auto

Auto-add SCCs to all bindings not marked INLINE [dynamic]

-fprof-auto-top

Auto-add SCCs to all top-level bindings not marked INLINE [dynamic]

-fprof-auto-exported

Auto-add SCCs to all exported bindings not marked INLINE [dynamic]

-fprof-cafs

Auto-add SCCs to all CAFs [dynamic]

-fno-prof-count-entries

Do not collect entry counts [dynamic]

-ticky

Turn on ticky-ticky profiling [dynamic]

PROGRAM COVERAGE OPTIONS

-fhpc

Turn on Haskell program coverage instrumentation [dynamic]

-hpcdir dir

Directory to deposit .mix files during compilation (default is .hpc) [dynamic]

HASKELL PRE-PROCESSOR OPTIONS

-F

Enable the use of a pre-processor (set with -pgmF) [dynamic]

C PRE-PROCESSOR OPTIONS

-cpp

Run the C pre-processor on Haskell source files [dynamic]

-Dsymbol=value

Define a symbol in the C pre-processor [dynamic]

-Usymbol

Undefine a symbol in the C pre-processor [dynamic]

-Idir

Add dir to the directory search list for #include files [dynamic]

CODE GENERATION OPTIONS

-fasm

Use the native code generator [dynamic]

-fllvm

Compile using the LLVM code generator [dynamic]

-fno-code

Omit code generation [dynamic]

-fwrite-interface

Always write interface files [dynamic]

-fbyte-code

Generate byte-code [dynamic]

-fobject-code

Generate object code [dynamic]

LINKING OPTIONS

-shared

Generate a shared library (as opposed to an executable) [dynamic]

-staticlib

On Darwin/OS X/iOS only, generate a standalone static library (as opposed to an executable). This is the usual way to compile for iOS. [dynamic]

-fPIC

Generate position-independent code (where available) [dynamic]

-dynamic

Use dynamic Haskell libraries (if available) [dynamic]

-dynamic-too

Build dynamic object files as well as static object files during compilation [dynamic]

-dyno

Set the output path for the dynamically linked objects [dynamic]

-dynosuf

Set the output suffix for dynamic object files [dynamic]

-dynload

Selects one of a number of modes for finding shared libraries at runtime. [dynamic]

-framework name

On Darwin/OS X/iOS only, link in the framework name. This option corresponds to the -framework option for Apple's Linker. [dynamic]

-framework-path name

On Darwin/OS X/iOS only, add dir to the list of directories searched for frameworks. This option corresponds to the -F option for Apple's Linker. [dynamic]

-llib

Link in library lib [dynamic]

-Ldir

Add dir to the list of directories searched for libraries [dynamic]

-main-is

Set main module and function [dynamic]

--mk-dll

DLL-creation mode (Windows only) [dynamic]

-no-hs-main

Don't assume this program contains main [dynamic]

-rtsopts, -rtsopts={none,some,all}

Control whether the RTS behaviour can be tweaked via command-line flags and the GHCRTS environment variable. Using none means no RTS flags can be given; some means only a minimum of safe options can be given (the default), and all (or no argument at all) means that all RTS flags are permitted. [dynamic]

-with-rtsopts=opts

Set the default RTS options to opts. [dynamic]

-no-link

Omit linking [dynamic]

-split-objs

Split objects (for libraries) [dynamic]

-static

Use static Haskell libraries [dynamic]

-threaded

Use the threaded runtime [dynamic]

-debug

Use the debugging runtime [dynamic]

-ticky

For linking, this simply implies -debug; see . [dynamic]

-eventlog

Enable runtime event tracing [dynamic]

-fno-gen-manifest

Do not generate a manifest file (Windows only) [dynamic]

-fno-embed-manifest

Do not embed the manifest in the executable (Windows only) [dynamic]

-fno-shared-implib

Don't generate an import library for a DLL (Windows only) [dynamic]

-dylib-install-name path

Set the install name (via -install_name passed to Apple's linker), specifying the full install path of the library file. Any libraries or executables that link with it later will pick up that path as their runtime search location for it. (Darwin/OS X only) [dynamic]

-rdynamic

This instructs the linker to add all symbols, not only used ones, to the dynamic symbol table. Currently Linux and Windows/MinGW32 only. This is equivalent to using -optl -rdynamic on Linux, and -optl -export-all-symbols on Windows. [dynamic]

PLUGIN OPTIONS

-fplugin=module

Load a plugin exported by a given module [dynamic]

-fplugin-opt=module:args

Give arguments to a plugin module; module must be specified with -fplugin [dynamic]

REPLACING PHASES

-pgmL cmd

Use cmd as the literate pre-processor [dynamic]

-pgmP cmd

Use cmd as the C pre-processor (with -cpp only) [dynamic]

-pgmc cmd

Use cmd as the C compiler [dynamic]

-pgmlo cmd

Use cmd as the LLVM optimiser [dynamic]

-pgmlc cmd

Use cmd as the LLVM compiler [dynamic]

-pgms cmd

Use cmd as the splitter [dynamic]

-pgma cmd

Use cmd as the assembler [dynamic]

-pgml cmd

Use cmd as the linker [dynamic]

-pgmdll cmd

Use cmd as the DLL generator [dynamic]

-pgmF cmd

Use cmd as the pre-processor (with -F only) [dynamic]

-pgmwindres cmd

Use cmd as the program for embedding manifests on Windows. [dynamic]

-pgmlibtool cmd

Use cmd as the command for libtool (with -staticlib only). [dynamic]

-pgmreadelf cmd

Use cmd as the command for readelf (part of Unix binutils) [dynamic]

FORCING OPTIONS TO PARTICULAR PHASES

-optL option

pass option to the literate pre-processor [dynamic]

-optP option

pass option to cpp (with -cpp only) [dynamic]

-optF option

pass option to the custom pre-processor [dynamic]

-optc option

pass option to the C compiler [dynamic]

-optlo option

pass option to the LLVM optimiser [dynamic]

-optlc option

pass option to the LLVM compiler [dynamic]

-opta option

pass option to the assembler [dynamic]

-optl option

pass option to the linker [dynamic]

-optdll option

pass option to the DLL generator [dynamic]

-optwindres option

pass option to windres. [dynamic]

PLATFORM-SPECIFIC OPTIONS

-msse2

(x86 only) Use SSE2 for floating point [dynamic]

COMPILER DEBUGGING OPTIONS

-dcore-lint

Turn on internal sanity checking [dynamic]

-ddump-to-file

Dump to files instead of stdout [dynamic]

-ddump-asm

Dump assembly [dynamic]

-ddump-bcos

Dump interpreter byte code [dynamic]

-ddump-cmm

Dump C-- output [dynamic]

-ddump-core-stats

Print a one-line summary of the size of the Core program at the end of the optimisation pipeline [dynamic]

-ddump-cse

Dump CSE output [dynamic]

-ddump-deriv

Dump deriving output [dynamic]

-ddump-ds

Dump desugarer output [dynamic]

-ddump-foreign

Dump foreign export stubs [dynamic]

-ddump-hpc

Dump after instrumentation for program coverage [dynamic]

-ddump-inlinings

Dump inlining info [dynamic]

-ddump-llvm

Dump LLVM intermediate code [dynamic]

-ddump-occur-anal

Dump occurrence analysis output [dynamic]

-ddump-opt-cmm

Dump the results of C-- to C-- optimising passes [dynamic]

-ddump-parsed

Dump parse tree [dynamic]

-ddump-prep

Dump prepared core [dynamic]

-ddump-rn

Dump renamer output [dynamic]

-ddump-rule-firings

Dump rule firing info [dynamic]

-ddump-rule-rewrites

Dump detailed rule firing info [dynamic]

-ddump-rules

Dump rules [dynamic]

-ddump-vect

Dump vectoriser input and output [dynamic]

-ddump-simpl

Dump final simplifier output [dynamic]

-ddump-simpl-iterations

Dump output from each simplifier iteration [dynamic]

-ddump-spec

Dump specialiser output [dynamic]

-ddump-splices

Dump TH spliced expressions, and what they evaluate to [dynamic]

-ddump-stg

Dump final STG [dynamic]

-ddump-stranal

Dump strictness analyser output [dynamic]

-ddump-strsigs

Dump strictness signatures [dynamic]

-ddump-tc

Dump typechecker output [dynamic]

-dth-dec-file

Show evaluated TH declarations in a .th.hs file [dynamic]

-ddump-types

Dump type signatures [dynamic]

-ddump-worker-wrapper

Dump worker-wrapper output [dynamic]

-ddump-if-trace

Trace interface files [dynamic]

-ddump-tc-trace

Trace typechecker [dynamic]

-ddump-vt-trace

Trace vectoriser [dynamic]

-ddump-rn-trace

Trace renamer [dynamic]

-ddump-rn-stats

Renamer stats [dynamic]

-ddump-simpl-stats

Dump simplifier stats [dynamic]

-dno-debug-output

Suppress unsolicited debugging output [static]

-dppr-debug

Turn on debug printing (more verbose) [static]

-dppr-user-length

Set the depth for printing expressions in error msgs [dynamic]

-dppr-colsNNN

Set the width of debugging output. For example -dppr-cols200 [dynamic]

-dppr-case-as-let

Print single alternative case expressions as strict lets. [dynamic]

-dsuppress-all

In core dumps, suppress everything (except for uniques) that is suppressible. [dynamic]

-dsuppress-uniques

Suppress the printing of uniques in debug output (easier to use diff) [dynamic]

-dsuppress-idinfo

Suppress extended information about identifiers where they are bound [dynamic]

-dsuppress-module-prefixes

Suppress the printing of module qualification prefixes [dynamic]

-dsuppress-type-signatures

Suppress type signatures [dynamic]

-dsuppress-type-applications

Suppress type applications [dynamic]

-dsuppress-coercions

Suppress the printing of coercions in Core dumps to make them shorter [dynamic]

-dsource-stats

Dump haskell source stats [dynamic]

-dcmm-lint

C-- pass sanity checking [dynamic]

-dstg-lint

STG pass sanity checking [dynamic]

-dstg-stats

Dump STG stats [dynamic]

-dverbose-core2core

Show output from each core-to-core pass [dynamic]

-dverbose-stg2stg

Show output from each STG-to-STG pass [dynamic]

-dshow-passes

Print out each pass name as it happens [dynamic]

-dfaststring-stats

Show statistics for fast string usage when finished [dynamic]

-frule-check

Report sites with rules that could have fired but didn't. Takes a string argument. [dynamic]

MISC COMPILER OPTIONS

-jN

When compiling with --make, compile N modules in parallel. [dynamic]

-fno-hi-version-check

Don't complain about .hi file mismatches [dynamic]

-fhistory-size

Set simplification history size [dynamic]

-fno-ghci-history

Do not use the load/store the GHCi command history from/to ghci_history. [dynamic]

-fno-ghci-sandbox

Turn off the GHCi sandbox. Means computations are run in the main thread, rather than a forked thread. [dynamic]

FILES

/usr/lib

COPYRIGHT

Copyright 2002, The University Court of the University of Glasgow.
All rights reserved.

AUTHOR

This manual page was generated from the XML documentation of GHC with blood, sweat, tears and a breaks-if-you-look-at-it-the-wrong-way XSL stylesheet originally written by Michael Weber <[email protected]> for the Debian GNU/Linux system (but may be used by others).