Changeset 72137 in vbox for trunk/src/VBox

Timestamp:

May 7, 2018 12:31:41 PM (7 years ago)

Author:

vboxsync

Message:

Some more fixes for building backwards-compatible Linux Additions binaries.
bugref:9112: Linux Additions: fix building binaries for older Linux user space

• Only link with --hash-style=sysv where that option is supported.
• Fix chk_stubs.c build mess by building it as a normal source file. It does

not need to come after the static libraries using its symbols on the command
line as it is an object file, not a library, and therefore its symbols are
always pulled in.

Location:

trunk/src/VBox/Additions/x11/VBoxClient

Files:

• Makefile.kmk (modified) (2 diffs)
• chk_stubs.c (modified) (1 diff)

trunk/src/VBox/Additions/x11/VBoxClient/Makefile.kmk

@@ -39 +39 @@
         display-svga.cpp \
         display-svga-x11.cpp
+VBoxClient_SOURCES.linux = \
+        chk_stubs.c
 VBoxClient_LIBPATH = \
         $(VBOX_LIBPATH32_X11)
@@ -68 +70 @@
         supc++ \
         gcc_eh
-# This has to be in LIBS, so as to be linked in after supc++ and gcc_eh, which
-# depend on the symbols it provides.  Static supc++ and gcc_eh on at least
-# Ubuntu 17.04 contain references to __sprintf_chk and __stack_chk_fail.
-# Furthermore, they contain references to memcpy, which needs to be resolved
-# to memcpy@GLIBC_2.2.5, which we solve in a not-very-satisfactory way with a
-# wrapper.
-##
-## @todo r=bird: With all due respect, what are you smoking??  The above does not compute,
-## so there is either some other reason which you fail to describe or you've got it all wrong.
-## It cannot be for reasons of symbol resolution, because puttin chk_stubs.c in SOURCES would
-## make absolutely sure the symbols in it would always be part of the link and present in the
-## symbol table before any library searching is done.  I cannot see how the --wrap-memcpy could
-## have anything to do with this either.
-##
-## Your query on IRC why chk_stubs.c is treated as C++, that's because the linker is called g++.
-##
-## Please explain why this nonsese is required or I will revert it and leave you deal with the consequences.
-##
-## -bird
-##
+
+# This forces the memcpy references in the static libraries to go to
+# __wrap_memcpy, which we can wrap around memcpy@GLIBC_2.2.5.  I do not know
+# how else to do that without recompiling or implementing our own memcpy.
 ifeq ($(KBUILD_TARGET),linux)
-VBoxClient_LIBS    += \
-        $(PATH_ROOT)/src/VBox/Additions/x11/VBoxClient/chk_stubs.c
 VBoxClient_LDFLAGS.amd64 += \
         -Wl,--wrap=memcpy

trunk/src/VBox/Additions/x11/VBoxClient/chk_stubs.c

@@ -50 +50 @@
  * supc++ and gcc_eh contain references which we cannot change. */
 
-#ifdef __cplusplus
-extern "C" void *__wrap_memcpy(void *dest, const void *src, size_t n);
-#endif
+extern void *__wrap_memcpy(void *dest, const void *src, size_t n);
 
 asm (".symver memcpy, memcpy@GLIBC_2.2.5");