[PATCH 3/5] Add d_main_name to dlang.c

[Iain Buclaw <ibuclaw at gdcproject dot org>]

The main program in D is _Dmain (demangled as 'D main') not C 'main'.
So the logical entry point of the program should be set accordingly.

2014-01-09  Iain Buclaw  <ibuclaw@gdcproject.org>

        * d-lang.h (d_main_name): Add declaration.
        * d-lang.c (d_main_name): New function.
        * symtab.c (find_main_name): Add call to d_main_name.

---

 gdb/ChangeLog |    6 ++++++
 gdb/d-lang.c  |   21 +++++++++++++++++++++
 gdb/d-lang.h  |    4 ++++
 gdb/symtab.c  |    7 +++++++
 4 files changed, 38 insertions(+)

diff --git a/gdb/d-lang.c b/gdb/d-lang.c
index 3775e4b..2b5f9c8 100644
--- a/gdb/d-lang.c
+++ b/gdb/d-lang.c
@@ -29,6 +29,27 @@
 
 #include <ctype.h>
 
+/* The name of the symbol to use to get the name of the main subprogram.  */
+static const char D_MAIN[] = "D main";
+
+/* Function returning the special symbol name used by D for the main
+   procedure in the main program if it is found in minimal symbol list.
+   This function tries to find minimal symbols so that it finds them even
+   if the program was compiled without debugging information.  */
+
+const char *
+d_main_name (void)
+{
+  struct minimal_symbol *msym;
+
+  msym = lookup_minimal_symbol (D_MAIN, NULL, NULL);
+  if (msym != NULL)
+    return D_MAIN;
+
+  /* No known entry procedure found, the main program is probably not D.  */
+  return NULL;
+}
+
 /* Extract identifiers from MANGLED_STR and append it to TEMPBUF.
    Return 1 on success or 0 on failure.  */
 static int
diff --git a/gdb/d-lang.h b/gdb/d-lang.h
index 8834a1d..9ede338 100644
--- a/gdb/d-lang.h
+++ b/gdb/d-lang.h
@@ -22,6 +22,10 @@
 
 #include "symtab.h"
 
+/* Defined in d-lang.c  */
+
+extern const char *d_main_name (void);
+
 extern char *d_demangle (const char *mangled, int options);
 
 extern void d_val_print (struct type *type, const gdb_byte *valaddr,
diff --git a/gdb/symtab.c b/gdb/symtab.c
index f215586..4bfff0a 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -5055,6 +5055,13 @@ find_main_name (void)
       return;
     }
 
+  new_main_name = d_main_name ();
+  if (new_main_name != NULL)
+    {
+      set_main_name (new_main_name);
+      return;
+    }
+
   new_main_name = go_main_name ();
   if (new_main_name != NULL)
     {