[commit: ghc] master: Always allow -staticlib (b8f33bc)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/b8f33bc6b738b0378976e42b79369f0e53b680c7/ghc

>---------------------------------------------------------------

commit b8f33bc6b738b0378976e42b79369f0e53b680c7
Author: Moritz Angermann <moritz.angermann at gmail.com>
Date:   Tue Jul 11 11:57:48 2017 -0400

    Always allow -staticlib
    
    the `-staticlib` flag is currently only supported on apple platforms,
    due to the avaiablity of libtool (the apple version, which is unlike the
    gnu version).  This however prevents the use of -staticlib in cases
    where it would be beneficial as well.  The functionality that
    `-staticlib` uses from `libtool` can be stubbed with a small script like
    the following:
    
    ```
    #!/bin/bash
    
    # This script pretends to be libtool.  And supports
    # only a limited set of flags.
    #
    # It is supposed to be a stand in for libtool -static, whic
    # creates a static archive.  This is done by locating all -l<lib>
    # libs in the provied -L<lib path> library paths, and building an
    # MRI script to create the final archive from all the libraries, and
    # other provided inputs.
    #
    
    name=${0##*/}
    target=${name%-*}
    
    set -e
    
    ldflags_L=()
    ldflags_l=()
    output=""
    inputs=()
    STATIC=0
    DYNAMIC=1
    mode=$DYNAMIC
    verbose=0
    
    # find_lib <name> path path path path
    function find_lib () {
            lib=$1; shift 1;
            for dir in $@; do
                    if [ -f "$dir/$lib" ]; then
                            echo "$dir/$lib"
                            break
                    fi
            done
    }
    
    while [ "$#" -gt 0 ]; do
            case "$1" in
                    -v|--verbose) verbose=1; shift 1;;
                    -o) output="$2"; shift 2;;
                    -L*) ldflags_L+=("${1:2:${#1}-2}"); shift 1;;
                    -l*) ldflags_l+=("lib${1:2:${#1}-2}.a"); shift 1;;
                    -static) mode=$STATIC; shift 1;;
                    -dynamic) mode=$DYNAMIC; shift 1;;
                    -Wl,*) ldflags+=("${1#*,}"); shift 1;;
                    -*) echo "unknown option: $1" >&2; exit 1;;
                    *) inputs+=("$1"); shift 1;;
            esac
    done
    
    if [ ! $mode == $STATIC ]; then
            echo "-dynamic not supported!" >&2; exit 1;
    fi
    
    MRI="create ${output}\n"
    for input in "${ldflags_l[@]}"; do
            lib=$(find_lib $input ${ldflags_L[@]})
            if [ -z $lib ]; then
                    echo "Failed to find lib $input" >&2
                    exit 1
            else
                    MRI+="addlib $lib\n"
                    continue
            fi
    done
    for input in "${inputs[@]}"; do
            MRI+="addmod $input\n"
    done
    MRI+="save\nend\n"
    echo -e "$MRI" | $target-ar -M
    $target-ranlib $output
    ```
    
    if `ar` supports MRI scripts.
    
    Reviewers: austin, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie
    
    Differential Revision: https://phabricator.haskell.org/D3706


>---------------------------------------------------------------

b8f33bc6b738b0378976e42b79369f0e53b680c7
 compiler/main/DriverPipeline.hs          | 5 +----
 docs/users_guide/phases.rst              | 8 +++-----
 utils/mkUserGuidePart/Options/Linking.hs | 7 ++++---
 3 files changed, 8 insertions(+), 12 deletions(-)

diff --git a/compiler/main/DriverPipeline.hs b/compiler/main/DriverPipeline.hs
index eed66b2..ad0e0c8 100644
--- a/compiler/main/DriverPipeline.hs
+++ b/compiler/main/DriverPipeline.hs
@@ -2082,10 +2082,7 @@ linkDynLibCheck dflags o_files dep_packages
 
 linkStaticLibCheck :: DynFlags -> [String] -> [InstalledUnitId] -> IO ()
 linkStaticLibCheck dflags o_files dep_packages
- = do
-    when (platformOS (targetPlatform dflags) `notElem` [OSiOS, OSDarwin]) $
-      throwGhcExceptionIO (ProgramError "Static archive creation only supported on Darwin/OS X/iOS")
-    linkBinary' True dflags o_files dep_packages
+ = linkBinary' True dflags o_files dep_packages
 
 -- -----------------------------------------------------------------------------
 -- Running CPP
diff --git a/docs/users_guide/phases.rst b/docs/users_guide/phases.rst
index 1efe6a4..f35ba1b 100644
--- a/docs/users_guide/phases.rst
+++ b/docs/users_guide/phases.rst
@@ -539,11 +539,9 @@ for example).
 
 .. ghc-flag:: -staticlib
 
-    On Darwin/OS X/iOS only, link all passed files into a static library
-    suitable for linking into an iOS (when using a cross-compiler) or
-    Mac Xcode project. To control the name, use the :ghc-flag:`-o` ⟨name⟩ option
-    as usual. The default name is ``liba.a``. This should nearly always
-    be passed when compiling for iOS with a cross-compiler.
+    Link all passed files into a static library suitable for linking.
+    To control the name, use the :ghc-flag:`-o` ⟨name⟩ option
+    as usual. The default name is ``liba.a``.
 
 .. ghc-flag:: -L ⟨dir⟩
 
diff --git a/utils/mkUserGuidePart/Options/Linking.hs b/utils/mkUserGuidePart/Options/Linking.hs
index 9edc7c3..3142020 100644
--- a/utils/mkUserGuidePart/Options/Linking.hs
+++ b/utils/mkUserGuidePart/Options/Linking.hs
@@ -11,9 +11,10 @@ linkingOptions =
          }
   , flag { flagName = "-staticlib"
          , flagDescription =
-           "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."
+           "Generate a standalone static library (as opposed to an " ++
+           "executable). This is useful when cross compiling. The " ++
+           "library together with all its dependencies ends up in in a " ++
+           "single static library that can be linked against."
          , flagType = DynamicFlag
          }
   , flag { flagName = "-fPIC"