bpo-31354: Let configure --with-lto work on all builds
Allow configure --with-lto to apply to all builds, not just profile-opt builds.
Whether this is actually useful or not must be determined by the person
building CPython using their own toolchain.
My own quick test on x86_64 Debian 9 (gcc 6.3, binutils 2.28) seemed
to suggest that it wasn't, but I expect better toolchains can or will exist
at some point. The point is to allow it at all.
diff --git a/configure.ac b/configure.ac
index 9cded9f..88ab6a1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1282,9 +1282,8 @@
fi
# Enable LTO flags
-AC_SUBST(LTOFLAGS)
AC_MSG_CHECKING(for --with-lto)
-AC_ARG_WITH(lto, AS_HELP_STRING([--with-lto], [Enable Link Time Optimization in PGO builds. Disabled by default.]),
+AC_ARG_WITH(lto, AS_HELP_STRING([--with-lto], [Enable Link Time Optimization in any build. Disabled by default.]),
[
if test "$withval" != no
then
@@ -1319,6 +1318,8 @@
esac
;;
esac
+ CFLAGS="$CFLAGS $LTOFLAGS"
+ LDFLAGS="$LDFLAGS $LTOFLAGS"
fi
# Enable PGO flags.