dnl This Source Code Form is subject to the terms of the Mozilla Public dnl License, v. 2.0. If a copy of the MPL was not distributed with this dnl file, You can obtain one at http://mozilla.org/MPL/2.0/. dnl check if the build is using lto. This is really primitive and only detects llvm based dnl compilers right now. AC_DEFUN([MOZ_DOING_LTO], [ cat > conftest.c <<EOF int foo = 1; EOF $1=no if ${CC-cc} ${CFLAGS} -S conftest.c -o conftest.s >/dev/null 2>&1; then if grep '^target triple =' conftest.s; then $1=yes fi fi rm -f conftest.[cs] ])