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diff --git a/src/ChangeLog b/src/ChangeLog
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--- a/src/ChangeLog
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@@ -1,3 +1,44 @@
+2014-09-30  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Simplify stack-allocated Lisp objects, and make them more portable.
+        The build_local_string macro was used in two ways: (1) string
+        literals for which scoped allocation suffices, and (2) file name
+        components, where it's not safe in general to assume bounded-size
+        ASCII data.  Simplify by defining a new macro SCOPED_STRING that
+        allocates a block-scope string, and by using SCOPED_STRING for (1)
+        and build_string for (2).  Furthermore, actually use stack
+        allocation only for objects known to have sufficient alignment.
+        This simpler implementation means Emacs can make
+        USE_STACK_LISP_OBJECTS the default unless GC_MARK_STACK !=
+        GC_MAKE_GCPROS_NOOPS.
+        * lisp.h (GCALIGNED): Align even if !USE_STACK_LISP_OBJECTS,
+        for fewer differences among implementations.
+        (struct Lisp_String): Now GCALIGNED.
+        (USE_STACK_LISP_OBJECTS): Default to true, since the
+        implementation no longer insists on a nonempty GCALIGNED.
+        But make it false if GC_MARK_STACK != GC_MAKE_GCPROS_NOOPS.
+        (SCOPED_CONS_INITIALIZER): Remove, since it's no longer needed
+        separately.  Move definiens to scoped_cons.  The old definition
+        was incorrect when GCALIGNED was defined to be empty.
+        (union Aligned_String): New type.
+        (USE_STACK_CONS, USE_STACK_STRING): New constants, so that the
+        implementation ports to compilers that don't align strictly enough.
+        Don't worry about the union sizes; it's not worth bothering about.
+        (scoped_cons, scoped_list1, scoped_list3, scoped_list4):
+        Rewrite using USE_STACK_CONS.
+        (scoped_cons): Assume the use of union Aligned_Cons.
+        (lisp_string_size, make_local_string, build_local_string): Remove.
+        Unless otherwise specified, all callers of build_local_string
+        changed to use SCOPED_STRING.
+        (SCOPED_STRING): New macro.
+        * data.c (wrong_choice):
+        * menu.c (single_menu_item):
+        * process.c (Fformat_network_address):
+        Hoist use of SCOPED_STRING out of a scope, so that its returned
+        object lives long enough.
+        * fileio.c (Fexpand_file_name): Use build_string, not SCOPED_STRING,
+        as the string might be long or might not be ASCII.
+
 2014-09-29  Eli Zaretskii  <eliz@gnu.org>
 
         * msdos.c (internal_terminal_init): Bump version to 25.