From ee28064389194bb614e5d34118e8fd51aa0f7bf9 Mon Sep 17 00:00:00 2001 From: Lily Ballard Date: Sat, 18 Apr 2020 20:35:04 -0700 Subject: macvim: Clean up hybrid compilation environment MacVim compiles the Vim part using `/usr/bin/clang` and the GUI part using Xcode. The Xcode portion always uses Xcode's own SDK and we have no workable alternative. The Vim portion so far has been compiling using a hybrid compilation environment, where it uses the SDK for most stuff but picks up a bunch of library linker paths (including libSystem) by virtue of Ruby's LDFLAGS. This hybrid compilation environment meant that if the SDK headers referenced a symbol that the library itself didn't have, this could produce link errors. Previously we attempted to fix this by synthesizing an include path that contained just the one header from Nix's Libsystem that referenced the missing symbol, to get rid of the reference and allow linking to work again, but this was very hacky and runs the risk of future Xcode SDK changes producing the same errors with different headers, or of future SDK versions expecting the intercepted header to contain a definition that Nix's doesn't. This new approach is to just clean up the compilation environment such that the Vim portion is compiling against the Xcode SDK as well, by sanitizing the LDFLAGS produced by the configure script so it stops referencing Nix's versions of OS libraries. This means the resulting Vim binary no longer depends at runtime on Nix for anything except the scripting language support, but that's how it's been for the MacVim binary all along anyway, and this approach should keep us insulated against future Xcode SDK changes. --- pkgs/applications/editors/vim/macvim.nix | 44 ++++++++++++++++++------------ pkgs/applications/editors/vim/macvim.patch | 20 -------------- 2 files changed, 27 insertions(+), 37 deletions(-) (limited to 'pkgs/applications/editors/vim') diff --git a/pkgs/applications/editors/vim/macvim.nix b/pkgs/applications/editors/vim/macvim.nix index 2a13c0ea700f..93ec48e54e0d 100644 --- a/pkgs/applications/editors/vim/macvim.nix +++ b/pkgs/applications/editors/vim/macvim.nix @@ -22,14 +22,6 @@ let mkdir -p $out/bin ln -s /usr/bin/xcrun /usr/bin/xcodebuild /usr/bin/tiffutil /usr/bin/qlmanage $out/bin ''; - # I'm not really sure how configure finds Nix Libsystem, but we get link errors when using - # Xcode 11.4 if we're compiling against Xcode's SDK but using Nix Libsystem. We can't just pass - # Libsystem's includes though as that causes other issues, particularly with availability macros. - # This is a horrible hack but let's just pass the header that's causing problems. - fakeLibsystemInclude = runCommand "macvim-libsystem-include-shim" {} '' - mkdir -p $out/include/sys/_types - ln -s ${darwin.Libsystem}/include/sys/_types/_fd_def.h $out/include/sys/_types - ''; in stdenv.mkDerivation { @@ -74,7 +66,6 @@ stdenv.mkDerivation { "--with-tlib=ncurses" "--with-compiledby=Nix" "--disable-sparkle" - "LDFLAGS=-headerpad_max_install_names" ]; makeFlags = ''PREFIX=$(out) CPPFLAGS="-Wno-error"''; @@ -89,19 +80,12 @@ stdenv.mkDerivation { # This is unfortunate, but we need to use the same compiler as Xcode, # but Xcode doesn't provide a way to configure the compiler. - # - # If you're willing to modify the system files, you can do this: - # http://hamelot.co.uk/programming/add-gcc-compiler-to-xcode-6/ - # - # But we don't have that option. preConfigure = '' CC=/usr/bin/clang DEV_DIR=$(/usr/bin/xcode-select -print-path)/Platforms/MacOSX.platform/Developer configureFlagsArray+=( "--with-developer-dir=$DEV_DIR" - # Also pass `-g -O` because configure would add those if we weren't setting CFLAGS. - "CFLAGS=-g -O -isystem ${fakeLibsystemInclude}/include" ) '' # For some reason having LD defined causes PSMTabBarControl to fail at link-time as it @@ -111,8 +95,34 @@ stdenv.mkDerivation { '' ; + # Because we're building with system clang, this means we're building against Xcode's SDK and + # linking against system libraries. The configure script is picking up Nix Libsystem (via ruby) + # so we need to patch that out or we'll get linker issues. The MacVim binary built by Xcode links + # against the system anyway so it doesn't really matter that the Vim binary will too. If we + # decide that matters, we can always patch it back to the Nix libsystem post-build. + # It also picks up libiconv, libunwind, and objc4 from Nix. These seem relatively harmless but + # let's strip them out too. + # + # Note: If we do add a post-build install_name_tool patch, we need to add the + # "LDFLAGS=-headerpad_max_install_names" flag to configureFlags and either patch it into the + # Xcode project or pass it as a flag to xcodebuild as well. postConfigure = '' - substituteInPlace src/auto/config.mk --replace "PERL_CFLAGS =" "PERL_CFLAGS = -I${darwin.libutil}/include" + substituteInPlace src/auto/config.mk \ + --replace "PERL_CFLAGS =" "PERL_CFLAGS = -I${darwin.libutil}/include" \ + --replace " -L${stdenv.cc.libc}/lib" "" \ + --replace " -L${darwin.libobjc}/lib" "" \ + --replace " -L${darwin.libunwind}/lib" "" \ + --replace " -L${darwin.libiconv}/lib" "" + + # All the libraries we stripped have -osx- in their name as of this time. + # Assert now that this pattern no longer appears in config.mk. + ( # scope variable + while IFS="" read -r line; do + if [[ "$line" == LDFLAGS*-osx-* ]]; then + echo "WARNING: src/auto/config.mk contains reference to Nix osx library" >&2 + fi + done