Put bcache inside "namespace gdb"

This avoids a conflict with a system "struct bcache" on
Solaris (see e.g.
https://www.isi.edu/nsnam/archive/ns-users/webarch/2001/msg05393.html)

Note that the Solaris conflict for now only surfaces with
--enable-targets=all (which the build bot doesn't use).

gdb/ChangeLog:

2019-12-06  Christian Biesinger  <cbiesinger@google.com>

	* bcache.c: Put in namespace gdb.
	* bcache.h: Likewise.
	* gdbtypes.c (check_types_worklist): Update.
	(types_deeply_equal): Update.
	* macrotab.c (struct macro_table) <bcache>: Update.
	(new_macro_table): Update.
	* macrotab.h (struct bcache): Put this forward declaration
	inside namespace gdb.
	(new_macro_table): Update.
	* objfiles.h (struct objfile_per_bfd_storage) <filename_cache>:
	Update.
	<macro_cache>: Update.
	* psymtab.h: (psymtab_storage) <psymbol_cache>: Update.

Change-Id: I843d5e91f7ccb3db6d1099a8214c15a74510256f

gdb/ChangeLog

@@ -1,3 +1,19 @@
+2019-12-06  Christian Biesinger  <cbiesinger@google.com>
+
+	* bcache.c: Put in namespace gdb.
+	* bcache.h: Likewise.
+	* gdbtypes.c (check_types_worklist): Update.
+	(types_deeply_equal): Update.
+	* macrotab.c (struct macro_table) <bcache>: Update.
+	(new_macro_table): Update.
+	* macrotab.h (struct bcache): Put this forward declaration
+	inside namespace gdb.
+	(new_macro_table): Update.
+	* objfiles.h (struct objfile_per_bfd_storage) <filename_cache>:
+	Update.
+	<macro_cache>: Update.
+	* psymtab.h: (psymtab_storage) <psymbol_cache>: Update.
+
 2019-12-06  Tom de Vries  <tdevries@suse.de>
 
 	PR symtab/24971

gdb/bcache.c

@@ -25,6 +25,8 @@
 
 #include <algorithm>
 
+namespace gdb {
+
 /* The type used to hold a single bcache string.  The user data is
    stored in d.data.  Since it can be any type, it needs to have the
    same alignment as the most strict alignment of any type on the host
@@ -378,3 +380,5 @@ bcache::memory_used ()
     return 0;
   return obstack_memory_used (&m_cache);
 }
+
+} /* namespace gdb */

gdb/bcache.h

@@ -136,6 +136,8 @@
   
 */
 
+namespace gdb {
+
 struct bstring;
 
 struct bcache
@@ -222,4 +224,6 @@ private:
   void expand_hash_table ();
 };
 
+} /* namespace gdb */
+
 #endif /* BCACHE_H */

gdb/gdbtypes.c

@@ -3813,7 +3813,7 @@ check_types_equal (struct type *type1, struct type *type2,
 
 static bool
 check_types_worklist (std::vector<type_equality_entry> *worklist,
-		      struct bcache *cache)
+		      gdb::bcache *cache)
 {
   while (!worklist->empty ())
     {
@@ -3849,7 +3849,7 @@ types_deeply_equal (struct type *type1, struct type *type2)
   if (type1 == type2)
     return true;
 
-  struct bcache cache (nullptr, nullptr);
+  gdb::bcache cache (nullptr, nullptr);
   worklist.emplace_back (type1, type2);
   return check_types_worklist (&worklist, &cache);
 }

gdb/macrotab.c

@@ -40,7 +40,7 @@ struct macro_table
 
   /* The bcache we should use to hold macro names, argument names, and
      definitions, or zero if we should use xmalloc.  */
-  struct bcache *bcache;
+  gdb::bcache *bcache;
 
   /* The main source file for this compilation unit --- the one whose
      name was given to the compiler.  This is the root of the
@@ -1025,7 +1025,7 @@ macro_for_each_in_scope (struct macro_source_file *file, int line,
 
 
 struct macro_table *
-new_macro_table (struct obstack *obstack, struct bcache *b,
+new_macro_table (struct obstack *obstack, gdb::bcache *b,
 		 struct compunit_symtab *cust)
 {
   struct macro_table *t;

gdb/macrotab.h

@@ -23,9 +23,12 @@
 #include "gdbsupport/function-view.h"
 
 struct obstack;
-struct bcache;
 struct compunit_symtab;
 
+namespace gdb {
+struct bcache;
+}
+
 /* How do we represent a source location?  I mean, how should we
    represent them within GDB; the user wants to use all sorts of
    ambiguous abbreviations, like "break 32" and "break foo.c:32"
@@ -170,7 +173,7 @@ struct macro_source_file
    the same source location (although 'gcc -DFOO -UFOO -DFOO=2' does
    do that in GCC 4.1.2.).  */
 struct macro_table *new_macro_table (struct obstack *obstack,
-                                     struct bcache *bcache,
+                                     gdb::bcache *bcache,
 				     struct compunit_symtab *cust);
 
 

gdb/objfiles.h

@@ -244,11 +244,11 @@ struct objfile_per_bfd_storage
 
   /* Byte cache for file names.  */
 
-  struct bcache filename_cache;
+  gdb::bcache filename_cache;
 
   /* Byte cache for macros.  */
 
-  struct bcache macro_cache;
+  gdb::bcache macro_cache;
 
   /* The gdbarch associated with the BFD.  Note that this gdbarch is
      determined solely from BFD information, without looking at target

gdb/psymtab.h

@@ -120,7 +120,7 @@ public:
   /* A byte cache where we can stash arbitrary "chunks" of bytes that
      will not change.  */
 
-  struct bcache psymbol_cache;
+  gdb::bcache psymbol_cache;
 
   /* Vectors of all partial symbols read in from file.  The actual data
      is stored in the objfile_obstack.  */