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-rw-r--r--sysdeps/generic/initfini.c138
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diff --git a/sysdeps/generic/initfini.c b/sysdeps/generic/initfini.c
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+/* Special .init and .fini section support.
+ Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it
+ and/or modify it under the terms of the GNU Library General Public
+ License as published by the Free Software Foundation; either
+ version 2 of the License, or (at your option) any later version.
+
+ In addition to the permissions in the GNU Library General Public
+ License, the Free Software Foundation gives you unlimited
+ permission to link the compiled version of this file with other
+ programs, and to distribute those programs without any restriction
+ coming from the use of this file. (The Library General Public
+ License restrictions do apply in other respects; for example, they
+ cover modification of the file, and distribution when not linked
+ into another program.)
+
+ The GNU C Library is distributed in the hope that it will be
+ useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+/* This file is compiled into assembly code which is then munged by a sed
+ script into two files: crti.s and crtn.s.
+
+ * crti.s puts a function prologue at the beginning of the
+ .init and .fini sections and defines global symbols for
+ those addresses, so they can be called as functions.
+
+ * crtn.s puts the corresponding function epilogues
+ in the .init and .fini sections. */
+
+#include <stdlib.h>
+
+/* We use embedded asm for .section unconditionally, as this makes it
+ easier to insert the necessary directives into crtn.S. */
+#define SECTION(x) asm (".section " x );
+
+/* Embed an #include to pull in the alignment and .end directives. */
+asm ("\n#include \"defs.h\"");
+
+/* The initial common code ends here. */
+asm ("\n/*@HEADER_ENDS*/");
+
+/* To determine whether we need .end and .align: */
+asm ("\n/*@TESTS_BEGIN*/");
+void
+dummy (void (*foo) (void))
+{
+ if (foo)
+ (*foo) ();
+}
+asm ("\n/*@TESTS_END*/");
+
+/* The beginning of _init: */
+asm ("\n/*@_init_PROLOG_BEGINS*/");
+
+SECTION (".init")
+void
+_init (void)
+{
+ /* We cannot use the normal constructor mechanism in gcrt1.o because it
+ appears before crtbegin.o in the link, so the header elt of .ctors
+ would come after the elt for __gmon_start__. One approach is for
+ gcrt1.o to reference a symbol which would be defined by some library
+ module which has a constructor; but then user code's constructors
+ would come first, and not be profiled. */
+ extern void __gmon_start__ (void) __attribute__ ((weak)); /*weak_extern (__gmon_start__);*/
+
+#ifndef WEAK_GMON_START
+ __gmon_start__ ();
+#else
+ if (__gmon_start__)
+ __gmon_start__ ();
+#endif
+
+ asm ("ALIGN");
+ asm("END_INIT");
+ /* Now the epilog. */
+ asm ("\n/*@_init_PROLOG_ENDS*/");
+ asm ("\n/*@_init_EPILOG_BEGINS*/");
+ SECTION(".init");
+}
+asm ("END_INIT");
+#ifndef WEAK_GMON_START
+SECTION(".text");
+
+/* This version of __gmon_start__ is used if no other is found. By providing
+ a default function we avoid the need to test whether the pointer is NULL,
+ which can be painful on some machines. */
+
+void __attribute__ ((weak))
+__gmon_start__ (void)
+{
+ /* do nothing */
+}
+#endif
+
+/* End of the _init epilog, beginning of the _fini prolog. */
+asm ("\n/*@_init_EPILOG_ENDS*/");
+asm ("\n/*@_fini_PROLOG_BEGINS*/");
+
+SECTION (".fini")
+void
+_fini (void)
+{
+
+ /* End of the _fini prolog. */
+ asm ("ALIGN");
+ asm ("END_FINI");
+ asm ("\n/*@_fini_PROLOG_ENDS*/");
+
+ {
+ /* Let GCC know that _fini is not a leaf function by having a dummy
+ function call here. We arrange for this call to be omitted from
+ either crt file. */
+ extern void i_am_not_a_leaf (void);
+ i_am_not_a_leaf ();
+ }
+
+ /* Beginning of the _fini epilog. */
+ asm ("\n/*@_fini_EPILOG_BEGINS*/");
+ SECTION (".fini");
+}
+asm ("END_FINI");
+
+/* End of the _fini epilog. Any further generated assembly (e.g. .ident)
+ is shared between both crt files. */
+asm ("\n/*@_fini_EPILOG_ENDS*/");
+asm ("\n/*@TRAILER_BEGINS*/");
+
+/* End of file. */