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-rw-r--r--csu/Makefile36
-rw-r--r--csu/abi-note.S69
2 files changed, 87 insertions, 18 deletions
diff --git a/csu/Makefile b/csu/Makefile
index cba8a4a5f5..9664821ec4 100644
--- a/csu/Makefile
+++ b/csu/Makefile
@@ -36,25 +36,12 @@ omit-deps = $(patsubst %.o,%,$(start-installed-name) g$(start-installed-name) \
$(csu-dummies))
install-lib = $(start-installed-name) g$(start-installed-name) \
$(csu-dummies)
-distribute = initfini.c gmon-start.c start.c defs.awk
+distribute = initfini.c gmon-start.c start.c defs.awk abi-note.S abi-tag.h
all: # Make this the default target; it will be defined in Rules.
include ../Makeconfig
-ifneq ($(elf),yes)
-
-# When not using ELF, there is just one startfile, called crt0.o.
-start-installed-name = crt0.o
-
-else
-
-# In the ELF universe, crt0.o is called crt1.o, and there are
-# some additional bizarre files.
-start-installed-name = crt1.o
-have-initfini = yes
-
-endif
ifeq ($(have-initfini),yes)
@@ -75,7 +62,8 @@ $(objpfx)crt%.o: $(objpfx)crt%.S $(objpfx)defs.h
$(CC) -c -fPIC -g0 -I$(..) -I$(common-objpfx) -DASSEMBLER $< -o $@
$(objpfx)initfini.s: initfini.c
- $(CC) -S -fPIC -finhibit-size-directive $(no-exceptions) $< -o $@
+ $(CC) $(CPPFLAGS) $(CFLAGS) -g0 -S -fPIC -finhibit-size-directive \
+ $(no-exceptions) $< -o $@
$(objpfx)crti.S: $(objpfx)initfini.s
sed -n -e '1,/@HEADER_ENDS/p' \
@@ -95,19 +83,31 @@ endif
include ../Rules
+define link-relocatable
+$(CC) -nostdlib -nostartfiles -r -o $@ $^
+endef
+
ifndef start-installed-name-rule
+ifeq (yes,$(elf))
+# We link the ELF startfile along with a SHT_NOTE section indicating
+# the the kernel ABI the binaries linked with this library will require.
+$(objpfx)$(start-installed-name): $(objpfx)start.o $(objpfx)abi-note.o
+ $(link-relocatable)
+else
# The startfile is installed under different names, so we just call our
# source file `start.c' and copy to the installed name after compiling.
$(objpfx)$(start-installed-name): $(objpfx)start.o
- -rm -f $@
+ rm -f $@
ln $< $@
endif
+endif
# The profiling startfile is made by linking together the normal
# startfile with gmon-start.o, which defines a constructor function
# to turn on profiling code at startup.
-$(objpfx)g$(start-installed-name): $(objpfx)start.o $(objpfx)gmon-start.o
- $(CC) -nostdlib -nostartfiles -r -o $@ $^
+$(objpfx)g$(start-installed-name): $(objpfx)$(start-installed-name) \
+ $(objpfx)gmon-start.o
+ $(link-relocatable)
# These extra files are sometimes expected by system standard linking
# procedures, but we have nothing for them to do. So compile empty files.
diff --git a/csu/abi-note.S b/csu/abi-note.S
new file mode 100644
index 0000000000..baa409de4d
--- /dev/null
+++ b/csu/abi-note.S
@@ -0,0 +1,69 @@
+/* Special .init and .fini section support.
+ Copyright (C) 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. */
+
+#include <sysdep.h>
+
+/* The basic layout of note sections is specified by the ELF format. */
+
+#define ELF_NOTE_BEGIN(sectname, sectflags, type, name) \
+ .section sectname, sectflags; \
+ .align ALIGNARG(2); /* Notes are 4-byte aligned. */ \
+ .long 1f - 0f; /* 32-bit word: length of name field */ \
+ .long 3f - 2f; /* 32-bit word: length of desc field */ \
+ .long (type); /* 32-bit word: vendor-defined type field */ \
+0: .asciz name; /* null-terminated string, any length: name */\
+1: .align ALIGNARG(2); /* Name data padded to 4-byte alignment. */ \
+2: /* Here follows the "note descriptor" data, whose format \
+ is not specified by ELF. The vendor name and type field \
+ indicate what sort of data is found here. */
+
+#define ELF_NOTE_END \
+3: .align ALIGNARG(2) /* Pad to 4-byte align the next note. */
+
+
+/* The linker (GNU ld 2.8 and later) recognize an allocated section whose
+ name begins with `.note' and creates a PT_NOTE program header entry
+ pointing at it.
+
+ Such a program header is the canonical way (at least in the free OS
+ community) to identify the OS environment ABI that the executable was
+ created for. The ELF note information identifies a particular OS or
+ coordinated development effort within which the ELF header's e_machine
+ value plus (for dynamically linked programs) the PT_INTERP dynamic
+ linker name and DT_NEEDED shared library names fully identify the
+ runtime environment required by an executable.
+
+ The GNU project and cooperating development efforts (including the Linux
+ community) use a vendor name string of "GNU", and a note type field with
+ value 1 for a note descriptor that indicates ABI requirements. */
+
+#include <abi-tag.h> /* OS-specific ABI tag value */
+
+ELF_NOTE_BEGIN(".note.ABI-tag", "a", 1, "GNU")
+ .long ABI_TAG
+ELF_NOTE_END