+ // Fast lookup information for a given language.
+
+ // We map from exact match strings to Version_tree's. Historically
+ // version scripts sometimes have the same symbol multiple times,
+ // which is ambiguous. We warn about that case by storing the
+ // second Version_tree we see.
+ struct Version_tree_match
+ {
+ Version_tree_match(const Version_tree* r, bool ig,
+ const Version_expression* e)
+ : real(r), is_global(ig), expression(e), ambiguous(NULL)
+ { }
+
+ // The Version_tree that we return.
+ const Version_tree* real;
+ // True if this is a global match for the REAL member, false if it
+ // is a local match.
+ bool is_global;
+ // Point back to the Version_expression for which we created this
+ // match.
+ const Version_expression* expression;
+ // If not NULL, another Version_tree that defines the symbol.
+ const Version_tree* ambiguous;
+ };
+
+ // Map from an exact match string to a Version_tree.
+
+ typedef Unordered_map<std::string, Version_tree_match> Exact;
+