[arm] Allow explicit periods to be escaped in

The MULTILIB_REUSE mapping rules are built up using periods to
represent the placement of '=' signs in the command line syntax.  This
presents a problem if the option contains an explicit period because
that is translated unconditionally.  The result is that it is not
currently possible to write a reuse rule that would match the
ARMv8-M mainline architecture:

	-march=armv8-m.main

To fix this, this patch allows an explicit period to be escaped by writing
\. and by then preserving the period into the generated multilib header.

	* genmultilib (multilib_reuse): Allow an explicit period to be escaped
	with a backslash.  Remove the backslash after substituting unescaped
	periods.
	* doc/fragments.texi (MULTILIB_REUSE): Document it.

From-SVN: r249298

1 files changed, 2 insertions, 2 deletions

diff --git a/gcc/genmultilib b/gcc/genmultilib
index 2501f54..c8bcdf3 100644
--- a/gcc/genmultilib
+++ b/gcc/genmultilib
@@ -466,8 +466,8 @@ echo "static const char *const multilib_reuse_raw[] = {"
 for rrule in ${multilib_reuse}; do
   # The left part of the rule are the options we used to build multilib.
   # The right part of the rule are the options that can reuse this multilib.
-  combo=`echo ${rrule} | sed -e 's/=.*$//' -e 's/\./=/g'`
-  copts=`echo ${rrule} | sed -e 's/^.*=//' -e 's/\./=/g'`
+  combo=`echo ${rrule} | sed -e 's/=.*$//' -e 's/\([^\\]\)\./\1=/g' -e 's/\\\././g'`
+  copts=`echo ${rrule} | sed -e 's/^.*=//' -e 's/\([^\\]\)\./\1=/g' -e 's/\\\././g'`
   # The variable ${combinations} are the option combinations we will build
   # multilib from.  If the combination in the left part of reuse rule isn't
   # in this variable, it means no multilib will be built for current reuse