[GN]: Support for loadable modules

build/toolchain/mac/BUILD.gn

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # TODO(brettw) Use "gcc_toolchain.gni" like the Linux toolchains. This requires
 # some enhancements since the commands on Mac are slightly different than on
 # Linux.
 
 import("../goma.gni")
 import("//build/config/ios/ios_sdk.gni")
@@ skipping 101 matching lines @@
       ]
       default_output_extension = ".a"
       output_prefix = "lib"
     }
 
     tool("solink") {
       dylib = "{{root_out_dir}}/{{target_output_name}}{{output_extension}}"  # eg "./libfoo.dylib"
       rspfile = dylib + ".rsp"
 
       # These variables are not built into GN but are helpers that implement
-      # (1) linking to produce a .so, (2) extracting the symbols from that file
-      # to a temporary file, (3) if the temporary file has differences from the
-      # existing .TOC file, overwrite it, otherwise, don't change it.
+      # (1) linking to produce a .dylib, (2) extracting the symbols from that
+      # file to a temporary file, (3) if the temporary file has differences from
+      # the existing .TOC file, overwrite it, otherwise, don't change it.
       #
       # As a special case, if the library reexports symbols from other dynamic
       # libraries, we always update the .TOC and skip the temporary file and
       # diffing steps, since that library always needs to be re-linked.
       tocname = dylib + ".TOC"
       temporary_tocname = dylib + ".tmp"
 
       does_reexport_command = "[ ! -e $dylib -o ! -e $tocname ] || otool -l $dylib | grep -q LC_REEXPORT_DYLIB"
 
       link_command = "$ld -shared {{ldflags}} -o $dylib -Wl,-filelist,$rspfile"
       if (is_component_build) {
         link_command += " -Wl,-install_name,@rpath/{{target_output_name}}{{output_extension}}"
       }
       link_command += " {{solibs}} {{libs}}"
 
       replace_command = "if ! cmp -s $temporary_tocname $tocname; then mv $temporary_tocname $tocname"
       extract_toc_command = "{ otool -l $dylib | grep LC_ID_DYLIB -A 5; nm -gP $dylib | cut -f1-2 -d' ' | grep -v U\$\$; true; }"
 
       command = "if $does_reexport_command ; then $link_command && $extract_toc_command > $tocname; else $link_command && $extract_toc_command > $temporary_tocname && $replace_command ; fi; fi"
 
       rspfile_content = "{{inputs_newline}}"
 
-      description = "SOLINK {{output}}"
+      description = "DYLINK {{output}}"
 
       # Use this for {{output_extension}} expansions unless a target manually
       # overrides it (in which case {{output_extension}} will be what the target
       # specifies).
       default_output_extension = ".dylib"
 
       output_prefix = "lib"
 
       # Since the above commands only updates the .TOC file when it changes, ask
       # Ninja to check if the timestamp actually changed to know if downstream
       # dependencies should be recompiled.
       restat = true
 
       # Tell GN about the output files. It will link to the dylib but use the
       # tocname for dependency management.
       outputs = [
         dylib,
         tocname,
       ]
       link_output = dylib
       depend_output = tocname
     }
 
+    #    tool("solink") {

[Bons, 2015/10/06 20:29:19]

This will be called solink with the above changed to dylink.

Or if we want to keep with gyp conventions, this would be named solink_module

+    #      sofile = "{{root_out_dir}}/{{target_output_name}}{{output_extension}}"  # eg "./libfoo.so"
+    #      rspfile = sofile + ".rsp"
+    #
+    #      link_command = "$ld -bundle {{ldflags}} -o $sofile -Wl,-filelist,$rspfile"
+    #      if (is_component_build) {
+    #        link_command += " -Wl,-install_name,@rpath/{{target_output_name}}{{output_extension}}"
+    #      }
+    #      link_command += " {{solibs}} {{libs}}"
+    #      command = link_command
+    #
+    #      rspfile_content = "{{inputs_newline}}"
+    #
+    #      description = "SOLINK {{output}}"
+    #
+    #      # Use this for {{output_extension}} expansions unless a target manually
+    #      # overrides it (in which case {{output_extension}} will be what the target
+    #      # specifies).
+    #      default_output_extension = ".so"
+    #
+    #      output_prefix = "lib"
+    #
+    #      outputs = [
+    #        sofile
+    #      ]
+    #    }
+
     tool("link") {
       outfile = "{{root_out_dir}}/{{target_output_name}}{{output_extension}}"
       rspfile = "$outfile.rsp"
       command = "$ld {{ldflags}} -o $outfile -Wl,-filelist,$rspfile {{solibs}} {{libs}}"
       description = "LINK $outfile"
       rspfile_content = "{{inputs_newline}}"
       outputs = [
         outfile,
       ]
     }
@@ skipping 70 matching lines @@
 }
 
 mac_toolchain("x64") {
   toolchain_cpu = "x64"
   toolchain_os = "mac"
   cc = "${goma_prefix}/gcc"
   cxx = "${goma_prefix}/g++"
   ld = cxx
   is_clang = false
 }