[PATCH] Use std::string in main_info

[Tom Tromey <tom@tromey.com>]

This changes main_info to use std::string.  It removes some manual
memory management.
---
 gdb/symtab.c | 22 +++++++---------------
 1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/gdb/symtab.c b/gdb/symtab.c
index 9d6ee388ca2..bd73c521b1a 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -104,16 +104,9 @@ static struct block_symbol
 
 struct main_info
 {
-  main_info () = default;
-
-  ~main_info ()
-  {
-    xfree (name_of_main);
-  }
-
   /* Name of "main".  */
 
-  char *name_of_main = nullptr;
+  std::string name_of_main;
 
   /* Language of "main".  */
 
@@ -6172,15 +6165,14 @@ set_main_name (const char *name, enum language lang)
 {
   struct main_info *info = get_main_info ();
 
-  if (info->name_of_main != NULL)
+  if (!info->name_of_main.empty ())
     {
-      xfree (info->name_of_main);
-      info->name_of_main = NULL;
+      info->name_of_main.clear ();
       info->language_of_main = language_unknown;
     }
   if (name != NULL)
     {
-      info->name_of_main = xstrdup (name);
+      info->name_of_main = name;
       info->language_of_main = lang;
     }
 }
@@ -6287,10 +6279,10 @@ main_name ()
 {
   struct main_info *info = get_main_info ();
 
-  if (info->name_of_main == NULL)
+  if (info->name_of_main.empty ())
     find_main_name ();
 
-  return info->name_of_main;
+  return info->name_of_main.c_str ();
 }
 
 /* Return the language of the main function.  If it is not known,
@@ -6301,7 +6293,7 @@ main_language (void)
 {
   struct main_info *info = get_main_info ();
 
-  if (info->name_of_main == NULL)
+  if (info->name_of_main.empty ())
     find_main_name ();
 
   return info->language_of_main;
-- 
2.39.1