GN: Use lib.unstripped rather than lib.stripped. Add a toolchain.gni

build/toolchain/gcc_toolchain.gni

Index: build/toolchain/gcc_toolchain.gni
diff --git a/build/toolchain/gcc_toolchain.gni b/build/toolchain/gcc_toolchain.gni
index 29b913759653962261e3e3d585c30dee95e2fa07..14a66e40f2771860589c1a828c56fbc98976f301 100644
--- a/build/toolchain/gcc_toolchain.gni
+++ b/build/toolchain/gcc_toolchain.gni
@@ -2,6 +2,8 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/toolchain/toolchain.gni")
+
 # This value will be inherited in the toolchain below.
 concurrent_links = exec_script("get_concurrent_links.py", [], "value")
 
@@ -34,6 +36,11 @@ concurrent_links = exec_script("get_concurrent_links.py", [], "value")
 #  - deps
 #      Just forwarded to the toolchain definition.
 #  - is_clang
+#      Whether to use clang instead of gcc.
+#  - strip
+#      Location of the strip executable. When specified, strip will be run on
+#      all shared libraries and executables as they are built. The pre-stripped
+#      artifacts will be put in lib.stripped/ and exe.stripped/.
 template("gcc_toolchain") {
   toolchain(target_name) {
     assert(defined(invoker.cc), "gcc_toolchain() must specify a \"cc\" value")
@@ -138,24 +145,34 @@ template("gcc_toolchain") {
     tool("solink") {
       soname = "{{target_output_name}}{{output_extension}}"  # e.g. "libfoo.so".
       sofile = "{{root_out_dir}}/$soname"  # Possibly including toolchain dir.
+      if (shlib_subdir != ".") {
+        sofile = "{{root_out_dir}}/$shlib_subdir/$soname"
+      }
       rspfile = sofile + ".rsp"
 
+      unstripped_sofile = sofile
+      if (defined(invoker.strip)) {
+        unstripped_sofile = "{{root_out_dir}}/lib.unstripped/$soname"
+      }
+
       # These variables are not built into GN but are helpers that implement
       # (1) linking to produce a .so, (2) extracting the symbols from that file
       # to a temporary file, (3) if the temporary file has differences from the
       # existing .TOC file, overwrite it, otherwise, don't change it.
       tocfile = sofile + ".TOC"
       temporary_tocname = sofile + ".tmp"
-      link_command =
-          "$ld -shared {{ldflags}} -o $sofile -Wl,-soname=$soname @$rspfile"
+
+      link_command = "$ld -shared {{ldflags}} -o $unstripped_sofile -Wl,-soname=$soname @$rspfile"
       assert(defined(readelf), "to solink you must have a readelf")
       assert(defined(nm), "to solink you must have an nm")
-      toc_command = "{ $readelf -d $sofile | grep SONAME ; $nm -gD -f p $sofile | cut -f1-2 -d' '; } > $temporary_tocname"
+      toc_command = "{ $readelf -d $unstripped_sofile | grep SONAME ; $nm -gD -f p $unstripped_sofile | cut -f1-2 -d' '; } > $temporary_tocname"
       replace_command = "if ! cmp -s $temporary_tocname $tocfile; then mv $temporary_tocname $tocfile; fi"
 
       command = "$link_command && $toc_command && $replace_command"
-      if (defined(invoker.postsolink)) {
-        command += " && " + invoker.postsolink
+      if (defined(invoker.strip)) {
+        strip_command =
+            "${invoker.strip} --strip-unneeded -o $sofile $unstripped_sofile"
+        command += " && " + strip_command
       }
       rspfile_content = "-Wl,--whole-archive {{inputs}} {{solibs}} -Wl,--no-whole-archive $solink_libs_section_prefix {{libs}} $solink_libs_section_postfix"
 
@@ -164,7 +181,7 @@ template("gcc_toolchain") {
       # 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"
+      default_output_extension = shlib_extension
       if (defined(invoker.default_output_extension)) {
         default_output_extension = invoker.default_output_extension
       }
@@ -182,27 +199,35 @@ template("gcc_toolchain") {
         sofile,
         tocfile,
       ]
-      if (defined(invoker.solink_outputs)) {
-        outputs += invoker.solink_outputs
+      if (sofile != unstripped_sofile) {
+        outputs += [ unstripped_sofile ]
       }
       link_output = sofile
       depend_output = tocfile
     }
 
     tool("link") {
-      outfile = "{{root_out_dir}}/{{target_output_name}}{{output_extension}}"
+      exename = "{{target_output_name}}{{output_extension}}"
+      outfile = "{{root_out_dir}}/$exename"
       rspfile = "$outfile.rsp"
-      command = "$ld {{ldflags}} -o $outfile -Wl,--start-group @$rspfile {{solibs}} -Wl,--end-group $libs_section_prefix {{libs}} $libs_section_postfix"
-      if (defined(invoker.postlink)) {
-        command += " && " + invoker.postlink
+      unstripped_outfile = outfile
+      if (defined(invoker.strip)) {
+        unstripped_outfile = "{{root_out_dir}}/exe.unstripped/$exename"
+      }
+
+      command = "$ld {{ldflags}} -o $unstripped_outfile -Wl,--start-group @$rspfile {{solibs}} -Wl,--end-group $libs_section_prefix {{libs}} $libs_section_postfix"
+      if (defined(invoker.strip)) {
+        strip_command =
+            "${invoker.strip} --strip-unneeded -o $outfile $unstripped_outfile"
+        command += " && " + strip_command
       }
       description = "LINK $outfile"
       rspfile_content = "{{inputs}}"
       outputs = [
         outfile,
       ]
-      if (defined(invoker.link_outputs)) {
-        outputs += invoker.link_outputs
+      if (outfile != unstripped_outfile) {
+        outputs += [ unstripped_outfile ]
       }
     }