* dcrt0.cc (cygwin_atexit): Change preceeding comment to reflect

API version numbers.
	* external.cc (cygwin_internal): disable setting cxx_malloc on 64 bit.
	Add CW_FIXED_ATEXIT case.
	* include/cygwin/version.h (CYGWIN_VERSION_API_MINOR): Bump.
	* include/sys/cygwin.h (cygwin_getinfo_types): Add CW_FIXED_ATEXIT.
	* lib/atexit.c (atexit): Test running Cygwin version by checking
	return value of cygwin_internal (CW_FIXED_ATEXIT).

winsup/cygwin/ChangeLog

@@ -1,3 +1,14 @@
+2014-11-06  Corinna Vinschen  <corinna@vinschen.de>
+
+	* dcrt0.cc (cygwin_atexit): Change preceeding comment to reflect
+	API version numbers.
+	* external.cc (cygwin_internal): disable setting cxx_malloc on 64 bit.
+	Add CW_FIXED_ATEXIT case.
+	* include/cygwin/version.h (CYGWIN_VERSION_API_MINOR): Bump.
+	* include/sys/cygwin.h (cygwin_getinfo_types): Add CW_FIXED_ATEXIT.
+	* lib/atexit.c (atexit): Test running Cygwin version by checking
+	return value of cygwin_internal (CW_FIXED_ATEXIT).
+
 2014-11-05  Corinna Vinschen  <corinna@vinschen.de>
 
 	* lib/atexit.c (atexit): Check for being linked into the executable.

winsup/cygwin/dcrt0.cc

@@ -1251,12 +1251,12 @@ cygwin__cxa_atexit (void (*fn)(void *), void *obj, void *dso_handle)
 }
 
 /* This function is only called for applications built with Cygwin versions
-   up to 1.7.32.  Starting with 1.7.33, atexit is a statically linked function
-   inside of libcygwin.a.  The reason is that the old method to fetch the
-   caller return address is unreliable given GCCs ability to perform tail call
-   elimination.  For the details, see the below comment.
-   The atexit replacement is defined in libcygwin.a to allow reliable access
-   to the correct DSO handle. */
+   up to API 0.279.  Starting with API 0.280 (Cygwin 1.7.33/1.8.6-2), atexit
+   is a statically linked function inside of libcygwin.a.  The reason is that
+   the old method to fetch the caller return address is unreliable given GCCs
+   ability to perform tail call elimination.  For the details, see the below
+   comment.  The atexit replacement is defined in libcygwin.a to allow reliable
+   access to the correct DSO handle. */
 extern "C" int
 cygwin_atexit (void (*fn) (void))
 {

winsup/cygwin/external.cc

@@ -243,11 +243,13 @@ cygwin_internal (cygwin_getinfo_types t, ...)
 	break;
 
       case CW_USER_DATA:
+#ifndef __x86_64__
 	/* This is a kludge to work around a version of _cygwin_common_crt0
 	   which overwrote the cxx_malloc field with the local DLL copy.
 	   Hilarity ensues if the DLL is not loaded like while the process
 	   is forking. */
 	__cygwin_user_data.cxx_malloc = &default_cygwin_cxx_malloc;
+#endif
 	res = (uintptr_t) &__cygwin_user_data;
 	break;
 
@@ -673,6 +675,10 @@ cygwin_internal (cygwin_getinfo_types t, ...)
 	}
 	break;
 
+      case CW_FIXED_ATEXIT:
+	res = 0;
+	break;
+
       default:
 	set_errno (ENOSYS);
     }

winsup/cygwin/include/cygwin/version.h

@@ -455,12 +455,13 @@ details. */
       277: Add setsockopt(SO_PEERCRED).
       278: Add quotactl.
       279: Export stime.
+      280: Static atexit in libcygwin.a, CW_FIXED_ATEXIT.
      */
 
      /* Note that we forgot to bump the api for ualarm, strtoll, strtoull */
 
 #define CYGWIN_VERSION_API_MAJOR 0
-#define CYGWIN_VERSION_API_MINOR 279
+#define CYGWIN_VERSION_API_MINOR 280
 
      /* There is also a compatibity version number associated with the
 	shared memory regions.  It is incremented when incompatible

winsup/cygwin/include/sys/cygwin.h

@@ -150,7 +150,8 @@ typedef enum
     CW_GETNSSSEP,
     CW_GETPWSID,
     CW_GETGRSID,
-    CW_CYGNAME_FROM_WINNAME
+    CW_CYGNAME_FROM_WINNAME,
+    CW_FIXED_ATEXIT
   } cygwin_getinfo_types;
 
 #define CW_LOCK_PINFO CW_LOCK_PINFO
@@ -208,6 +209,7 @@ typedef enum
 #define CW_GETPWSID CW_GETPWSID
 #define CW_GETGRSID CW_GETGRSID
 #define CW_CYGNAME_FROM_WINNAME CW_CYGNAME_FROM_WINNAME
+#define CW_FIXED_ATEXIT CW_FIXED_ATEXIT
 
 /* Token type for CW_SET_EXTERNAL_TOKEN */
 enum

winsup/cygwin/lib/atexit.c

@@ -9,11 +9,13 @@ Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
 details. */
 
 #include <stddef.h>
+#include <sys/cygwin.h>
 #include <windows.h>
 
 /* Statically linked replacement for the former cygwin_atexit.  We need
    the function here to be able to access the correct __dso_handle of the
    caller's DSO. */
+
 int
 atexit (void (*fn) (void))
 {
@@ -21,6 +23,7 @@ atexit (void (*fn) (void))
   extern void *__dso_handle;
   extern void *__ImageBase;
 
+  void *fixed_dso_handle = &__dso_handle;
   /* Check for being called from inside the executable.  If so, use NULL
      as __dso_handle.  This allows to link executables with GCC versions
      not providing __dso_handle in crtbegin{S}.o.  In this case our own
@@ -28,7 +31,19 @@ atexit (void (*fn) (void))
      __dso_handle always points to &__ImageBase, while the __dso_handle
      for executables provided by crtbegin.o usually points to NULL.
      That's what we remodel here. */
-  return __cxa_atexit ((void (*)(void*))fn, NULL,
-		       &__ImageBase == (void **) GetModuleHandleW (NULL)
-		       ? NULL : &__dso_handle);
+  if (&__ImageBase == (void **) GetModuleHandleW (NULL))
+    fixed_dso_handle = NULL;
+  /* With recent Cygwin versions starting with API version 0.280 we call
+     __cxa_atexit (which is actually the cygwin__cxa_atexit wrapper in
+     dcrt0.cc) with the address of __dso_handle since that's how g++ generates
+     calls to __cxa_atexit as well.  However, when running an application
+     built with this atexit under an older Cygwin version, the __cxa_atexit
+     entry point is the one from newlib, which expects the *value* of
+     __dso_handle.  So, check for the Cygwin version we're running under.
+     Older version prior to 0.280 don't know CW_FIXED_ATEXIT and return -1.
+     0.280 and later return 0. */
+  else if (cygwin_internal (CW_FIXED_ATEXIT) != 0)
+    fixed_dso_handle = __dso_handle;
+
+  return __cxa_atexit ((void (*)(void*))fn, NULL, fixed_dso_handle);
 }