https://gcc.gnu.org/ml/gcc-patches/2019-10/msg00942.html
In constifying some more of line-map I discovered gengtype didn't know mutable. Added thusly.
* gengtype-lex.l (CXX_KEYWORD): Add 'mutable'.
From-SVN: r276939
+2019-10-13 Nathan Sidwell <nathan@acm.org>
+
+ * gengtype-lex.l (CXX_KEYWORD): Add 'mutable'.
+
2019-10-13 Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE>
* doc/sourcebuild.texi (Test Directives, Add Options): Remove
/* Include '::' in identifiers to capture C++ scope qualifiers. */
ID {CID}({HWS}::{HWS}{CID})*
EOID [^[:alnum:]_]
-CXX_KEYWORD inline|public:|private:|protected:|template|operator|friend|static
+CXX_KEYWORD inline|public:|private:|protected:|template|operator|friend|static|mutable
%x in_struct in_struct_comment in_comment
%option warn noyywrap nounput nodefault perf-report