Force builds to use C++17 in standalone builds.
The C++ Style Guide [1] currently recommends C++17, but Chromium is
using C++20 for the most part. [2] Change standalone PDFium to use its
own BUILDCONFIG.gn, which overrides the C++ standard config to always
use C++17. This allows PDFium to roll DEPS for //build and get all the
benefits, without surprises to the C++ standard config.
Note that this does not control the build config when PDFium is
embedded in another project.
[1] https://google.github.io/styleguide/cppguide.html#C++_Version
[2] https://crbug.com/1284275
Bug: pdfium:1932
Change-Id: I6b56a392a2b8837504540d48155cb3797afc2df5
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/101970
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: K. Moon <kmoon@chromium.org>
diff --git a/.gn b/.gn
index 9d6330b..b2bf99d 100644
--- a/.gn
+++ b/.gn
@@ -2,7 +2,9 @@
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
-buildconfig = "//build/config/BUILDCONFIG.gn"
+# TODO(crbug.com/pdfium/1932): Switch back to //build/config/BUILDCONFIG.gn if
+# appropriate.
+buildconfig = "//build_overrides/BUILDCONFIG.gn"
# The python interpreter to use by default. On Windows, this will look
# for python3.exe and python3.bat.
