PR c++/55223
gcc/cp/
	* pt.c (tsubst_copy_and_build) [LAMBDA_EXPR]: Fix handling of
	default argument scope.
	* mangle.c (write_name): Likewise.
libiberty/
	* cp-demangle.c (d_dump): Handle DEMANGLE_COMPONENT_DEFAULT_ARG.
	(d_print_comp): Likewise.

From-SVN: r196065