[FYI] [PATCH] Fix compile error & incorrect push

[Christian Biesinger via gdb-patches]

I accidentally pushed the wrong version of the patch for commit
7bb43059820c5febb4509b15202a93efde442bc6 (where the review
comments were not fixed), and I did a bad conflict resolution
for ccb1ba62299edce72053dd567b9d384814e11885 leading to a
compile error when libxxhash is available. This fixes both
issues.

gdb/ChangeLog:

2019-10-22  Christian Biesinger  <cbiesinger@google.com>

	* symtab.c (struct demangled_name_entry): Add a constructor.
	(free_demangled_name_entry): New function to call the destructor
	for demangled_name_entry.
	(create_demangled_names_hash): Pass free_demangled_name_entry to
	htab_create_alloc.
	(symbol_set_names): Call placement new for demangled_name_entry.
	* utils.c: No longer include xxhash.h here, now that fast_hash
	is inlined in the header.
	* utils.h: Instead, include it here.

Change-Id: If776099d39a65a12733d42efcb859feca1b07a39
---
 gdb/ChangeLog | 12 ++++++++++++
 gdb/symtab.c  | 23 ++++++++++++++++++-----
 gdb/utils.c   |  4 ----
 gdb/utils.h   |  4 ++++
 4 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 3fac7952ad..8255a8540c 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,15 @@
+2019-10-22  Christian Biesinger  <cbiesinger@google.com>
+
+	* symtab.c (struct demangled_name_entry): Add a constructor.
+	(free_demangled_name_entry): New function to call the destructor
+	for demangled_name_entry.
+	(create_demangled_names_hash): Pass free_demangled_name_entry to
+	htab_create_alloc.
+	(symbol_set_names): Call placement new for demangled_name_entry.
+	* utils.c: No longer include xxhash.h here, now that fast_hash
+	is inlined in the header.
+	* utils.h: Instead, include it here.
+
 2019-10-22  Christian Biesinger  <cbiesinger@google.com>
 
 	* Makefile.in: Link with libxxhash.
diff --git a/gdb/symtab.c b/gdb/symtab.c
index dff92ca203..ed55cecc73 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -715,6 +715,9 @@ symbol_set_language (struct general_symbol_info *gsymbol,
 /* Objects of this type are stored in the demangled name hash table.  */
 struct demangled_name_entry
 {
+  demangled_name_entry (gdb::string_view mangled_name)
+    : mangled (mangled_name) {}
+
   gdb::string_view mangled;
   ENUM_BITFIELD(language) language : LANGUAGE_BITS;
   char demangled[1];
@@ -744,6 +747,15 @@ eq_demangled_name_entry (const void *a, const void *b)
   return da->mangled == db->mangled;
 }
 
+static void
+free_demangled_name_entry (void *data)
+{
+  struct demangled_name_entry *e
+    = (struct demangled_name_entry *) data;
+
+  e->~demangled_name_entry();
+}
+
 /* Create the hash table used for demangled names.  Each hash entry is
    a pair of strings; one for the mangled name and one for the demangled
    name.  The entry is hashed via just the mangled name.  */
@@ -758,7 +770,7 @@ create_demangled_names_hash (struct objfile_per_bfd_storage *per_bfd)
 
   per_bfd->demangled_names_hash.reset (htab_create_alloc
     (256, hash_demangled_name_entry, eq_demangled_name_entry,
-     NULL, xcalloc, xfree));
+     free_demangled_name_entry, xcalloc, xfree));
 }
 
 /* Try to determine the demangled name for a symbol, based on the
@@ -819,7 +831,6 @@ symbol_set_names (struct general_symbol_info *gsymbol,
   struct demangled_name_entry **slot;
   /* A 0-terminated copy of the linkage name.  */
   const char *linkage_name_copy;
-  struct demangled_name_entry entry;
 
   if (gsymbol->language == language_ada)
     {
@@ -857,7 +868,7 @@ symbol_set_names (struct general_symbol_info *gsymbol,
   else
     linkage_name_copy = linkage_name;
 
-  entry.mangled = gdb::string_view (linkage_name_copy, len);
+  struct demangled_name_entry entry (gdb::string_view (linkage_name_copy, len));
   slot = ((struct demangled_name_entry **)
 	  htab_find_slot (per_bfd->demangled_names_hash.get (),
 			  &entry, INSERT));
@@ -890,7 +901,8 @@ symbol_set_names (struct general_symbol_info *gsymbol,
 	       obstack_alloc (&per_bfd->storage_obstack,
 			      offsetof (struct demangled_name_entry, demangled)
 			      + demangled_len + 1));
-	  (*slot)->mangled = gdb::string_view (linkage_name, len);
+	  new (*slot) demangled_name_entry
+	    (gdb::string_view (linkage_name, len));
 	}
       else
 	{
@@ -906,7 +918,8 @@ symbol_set_names (struct general_symbol_info *gsymbol,
 			      + len + demangled_len + 2));
 	  mangled_ptr = &((*slot)->demangled[demangled_len + 1]);
 	  strcpy (mangled_ptr, linkage_name_copy);
-	  (*slot)->mangled = gdb::string_view (mangled_ptr, len);
+	  new (*slot) demangled_name_entry
+	    (gdb::string_view (mangled_ptr, len));
 	}
       (*slot)->language = gsymbol->language;
 
diff --git a/gdb/utils.c b/gdb/utils.c
index 1b62e55b57..3afb8e5945 100644
--- a/gdb/utils.c
+++ b/gdb/utils.c
@@ -36,10 +36,6 @@
 #include <pc.h>
 #endif
 
-#ifdef HAVE_LIBXXHASH
-#include <xxhash.h>
-#endif
-
 #include <signal.h>
 #include "gdbcmd.h"
 #include "serial.h"
diff --git a/gdb/utils.h b/gdb/utils.h
index a8ad9d9c86..e837621a2b 100644
--- a/gdb/utils.h
+++ b/gdb/utils.h
@@ -25,6 +25,10 @@
 #include "gdbsupport/scoped_restore.h"
 #include <chrono>
 
+#ifdef HAVE_LIBXXHASH
+#include <xxhash.h>
+#endif
+
 struct completion_match_for_lcd;
 class compiled_regex;
 
-- 
2.24.0.rc0.303.g954a862665-goog