Change dbxread.c to use type-safe registry

This changes dbxread.c to use the type-safe registry.  In a couple of
spots, you'll see that dbx_objfile_data_key.emplace is called but the
result is not used; this is because those functions refer to the key
via the various DBX_* macros.

2019-07-10  Tom Tromey  <tromey@adacore.com>

	* gdb-stabs.h (struct dbx_symfile_info): Add initializers and
	destructor.
	(dbx_objfile_data_key): Change type and declare later.
	(DBX_SYMFILE_INFO): Rewrite.
	* dbxread.c (dbx_objfile_data_key): Change type.
	(dbx_symfile_init): Update.
	(~dbx_symfile_info): Rename from dbx_free_symfile_info.  Update.
	(coffstab_build_psymtabs, elfstab_build_psymtabs)
	(stabsect_build_psymtabs, _initialize_dbxread): Update.

1 files changed, 21 insertions, 20 deletions

diff --git a/gdb/gdb-stabs.h b/gdb/gdb-stabs.h
index 3b64d32..dfdd20b 100644
--- a/gdb/gdb-stabs.h
+++ b/gdb/gdb-stabs.h
@@ -27,41 +27,42 @@
    each others' functions as required.  */
 
 
-/* The tag used to find the DBX info attached to an objfile.  This is
-   global because it is referenced by several modules.  */
-extern const struct objfile_data *dbx_objfile_data_key;
-
 /* Information is passed among various dbxread routines for accessing
    symbol files.  A pointer to this structure is kept in the objfile,
    using the dbx_objfile_data_key.  */
 
 struct dbx_symfile_info
   {
-    CORE_ADDR text_addr;	/* Start of text section */
-    int text_size;		/* Size of text section */
-    int symcount;		/* How many symbols are there in the file */
-    char *stringtab;		/* The actual string table */
-    int stringtab_size;		/* Its size */
-    file_ptr symtab_offset;	/* Offset in file to symbol table */
-    int symbol_size;		/* Bytes in a single symbol */
+    ~dbx_symfile_info ();
+
+    CORE_ADDR text_addr = 0;	/* Start of text section */
+    int text_size = 0;		/* Size of text section */
+    int symcount = 0;		/* How many symbols are there in the file */
+    char *stringtab = nullptr;		/* The actual string table */
+    int stringtab_size = 0;		/* Its size */
+    file_ptr symtab_offset = 0;	/* Offset in file to symbol table */
+    int symbol_size = 0;		/* Bytes in a single symbol */
 
     /* See stabsread.h for the use of the following.  */
-    struct header_file *header_files;
-    int n_header_files;
-    int n_allocated_header_files;
+    struct header_file *header_files = nullptr;
+    int n_header_files = 0;
+    int n_allocated_header_files = 0;
 
     /* Pointers to BFD sections.  These are used to speed up the building of
        minimal symbols.  */
-    asection *text_section;
-    asection *data_section;
-    asection *bss_section;
+    asection *text_section = nullptr;
+    asection *data_section = nullptr;
+    asection *bss_section = nullptr;
 
     /* Pointer to the separate ".stab" section, if there is one.  */
-    asection *stab_section;
+    asection *stab_section = nullptr;
   };
 
-#define DBX_SYMFILE_INFO(o) \
-  ((struct dbx_symfile_info *) objfile_data ((o), dbx_objfile_data_key))
+/* The tag used to find the DBX info attached to an objfile.  This is
+   global because it is referenced by several modules.  */
+extern objfile_key<dbx_symfile_info> dbx_objfile_data_key;
+
+#define DBX_SYMFILE_INFO(o)	(dbx_objfile_data_key.get (o))
 #define DBX_TEXT_ADDR(o)	(DBX_SYMFILE_INFO(o)->text_addr)
 #define DBX_TEXT_SIZE(o)	(DBX_SYMFILE_INFO(o)->text_size)
 #define DBX_SYMCOUNT(o)		(DBX_SYMFILE_INFO(o)->symcount)