gn: use root_build_dir instead of . for rebase_path

third_party/yasm/BUILD.gn

 # Copyright 2014 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.
 
 # The yasm build process creates a slew of small C subprograms that
 # dynamically generate files at various point in the build process.  This makes
 # the build integration moderately complex.
 #
 # There are three classes of dynamically generated files:
 #   1) C source files that should be included in the build (eg., lc3bid.c)
@@ skipping 103 matching lines @@
        "source/patched-yasm/tools/re2c/translate.c",
     ]
 
     configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [ ":yasm_config",
                  "//build/config/compiler:no_chromium_code" ]
 
     # re2c is missing CLOSEVOP from one switch.
     if (is_posix) {
       cflags = [ "-Wno-switch" ]
+    } else if (is_win) {
+      cflags = [ "/wd4267" ]  # size_t to int conversion.
     }
   }
 
   executable("yasm") {
     sources = [
       "source/patched-yasm/frontends/yasm/yasm-options.c",
       "source/patched-yasm/frontends/yasm/yasm.c",
       "source/patched-yasm/libyasm/assocdat.c",
       "source/patched-yasm/libyasm/bc-align.c",
       "source/patched-yasm/libyasm/bc-data.c",
@@ skipping 113 matching lines @@
   compiled_action_foreach("compile_gperf") {
     tool = ":genperf"
     sources = [
       "source/patched-yasm/modules/arch/x86/x86cpu.gperf",
       "source/patched-yasm/modules/arch/x86/x86regtmod.gperf",
     ]
 
     outputs = [ "$target_gen_dir/{{source_name_part}}.c" ]
     args = [
       "{{source}}",
-      rebase_path(target_gen_dir, ".") + "/{{source_name_part}}.c",
+      rebase_path(target_gen_dir, root_build_dir) + "/{{source_name_part}}.c",
     ]
     deps = [
       ":generate_x86_insn"
     ]
   }
 
   # This differs from |compile_gperf| in where it places it output files.
   compiled_action_foreach("compile_gperf_for_include") {
     tool = ":genperf"
     sources = [
       # Make sure the generated gperf files in $target_gen_dir are synced with
       # the outputs for the related generate_*_insn actions in the
       # generate_files target below.
       #
       # The output for these two are #included by
       #   source/patched-yasm/modules/arch/x86/x86id.c
       "$yasm_gen_include_dir/x86insn_gas.gperf",
       "$yasm_gen_include_dir/x86insn_nasm.gperf",
     ]
 
     outputs = [ "$yasm_gen_include_dir/{{source_name_part}}.c" ]
     args = [
       "{{source}}",
-      rebase_path(yasm_gen_include_dir, ".") + "/{{source_name_part}}.c",
+      rebase_path(yasm_gen_include_dir, root_build_dir) +
+          "/{{source_name_part}}.c",
     ]
     deps = [
       ":generate_x86_insn"
     ]
   }
 
   template("compile_macro") {
     compiled_action(target_name) {
       tool = ":genmacro"
       # Output #included by source/patched-yasm/frontends/yasm/yasm.c.
@@ skipping 44 matching lines @@
   compiled_action_foreach("compile_re2c") {
     tool = ":re2c"
     sources = [
       "source/patched-yasm/modules/parsers/gas/gas-token.re",
       "source/patched-yasm/modules/parsers/nasm/nasm-token.re",
     ]
     outputs = [ "$target_gen_dir/{{source_name_part}}.c" ]
     args = [
       "-b",
       "-o",
-      rebase_path(target_gen_dir, ".") + "/{{source_name_part}}.c",
+      rebase_path(target_gen_dir, root_build_dir) + "/{{source_name_part}}.c",
       "{{source}}",
     ]
   }
 
   # This call doesn't fit into the re2c template above.
   compiled_action("compile_re2c_lc3b") {
     tool = ":re2c"
     sources = [ "source/patched-yasm/modules/arch/lc3b/lc3bid.re" ]
     outputs = [ "$target_gen_dir/lc3bid.c" ]
     args = [
@@ skipping 41 matching lines @@
     script = "source/patched-yasm/modules/arch/x86/gen_x86_insn.py"
     # Output eventually #included by source/patched-yasm/frontends/yasm/x86id.c
     outputs = [
       "$yasm_gen_include_dir/x86insns.c",
       "$yasm_gen_include_dir/x86insn_gas.gperf",
       "$yasm_gen_include_dir/x86insn_nasm.gperf",
     ]
     args = [ rebase_path(yasm_gen_include_dir, root_build_dir) ]
   }
 }