Extract symbol-writing function from parsers

I noticed that several parsers shared the same code to write a symbol
reference to an expression.  This patch factors this code out into a
new function.

Regression tested on x86-64 Fedora 32.

gdb/ChangeLog
2021-02-05  Tom Tromey  <tom@tromey.com>

	* parser-defs.h (write_exp_symbol_reference): Declare.
	* parse.c (write_exp_symbol_reference): New function.
	* p-exp.y (variable): Use write_exp_symbol_reference.
	* m2-exp.y (variable): Use write_exp_symbol_reference.
	* f-exp.y (variable): Use write_exp_symbol_reference.
	* d-exp.y (PrimaryExpression): Use write_exp_symbol_reference.
	* c-exp.y (variable): Use write_exp_symbol_reference.

1 files changed, 10 insertions, 0 deletions

diff --git a/gdb/parser-defs.h b/gdb/parser-defs.h
index 5ff5d52..466230e 100644
--- a/gdb/parser-defs.h
+++ b/gdb/parser-defs.h
@@ -334,6 +334,16 @@ extern void write_exp_msymbol (struct expr_builder *,
 
 extern void write_dollar_variable (struct parser_state *, struct stoken str);
 
+/* Write a reference to a symbol to the expression being built in PS.
+   NAME is the name of the symbol to write; SYM is the symbol.  If SYM
+   is nullptr (meaning the 'symbol' member), a minimal symbol will be
+   searched for and used if available.  Throws an exception if SYM is
+   nullptr and no minimal symbol can be found.  */
+
+extern void write_exp_symbol_reference (struct parser_state *ps,
+					const char *name,
+					struct block_symbol sym);
+
 extern const char *find_template_name_end (const char *);
 
 extern std::string copy_name (struct stoken);