Fix extern symbols defined and not used

* src/alloc.c: Always include <signal.h>.
(malloc_warning) [!SIGDANGER && (SYSTEM_MALLOC || HYBRID_MALLOC)]:
Do not define; unused.
* src/emacs.c, src/lisp.h (might_dump) [!DOUG_LEA_MALLOC]: Now static.
* src/gmalloc.c (gdefault_morecore): Rename from __default_morecore,
to avoid collision with glibc.  Now static.  All uses changed.
* src/lastfile.c (my_edata): Define only if
((!defined SYSTEM_MALLOC && !defined HYBRID_MALLOC && !defined
WINDOWSNT) \ || defined CYGWIN || defined DARWIN_OS).
(Bug#22086)

1 files changed, 2 insertions, 0 deletions

diff --git a/src/lisp.h b/src/lisp.h
index cafcfdef438..ef86c4fc958 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -619,7 +619,9 @@ extern _Noreturn Lisp_Object wrong_type_argument (Lisp_Object, Lisp_Object);
 extern _Noreturn void wrong_choice (Lisp_Object, Lisp_Object);
 
 /* Defined in emacs.c.  */
+#ifdef DOUG_LEA_MALLOC
 extern bool might_dump;
+#endif
 /* True means Emacs has already been initialized.
    Used during startup to detect startup of dumped Emacs.  */
 extern bool initialized;