um: fix gcov build breakage

a) exports in gmon_syms.c duplicate kernel/gcov/* ones
b) excluding -pg in vdso compile is not enough - -fprofile-arcs
and -ftest-coverage also needs to be excluded
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

arch/um/kernel/gmon_syms.c

@@ -7,18 +7,3 @@
 
 extern void __bb_init_func(void *)  __attribute__((weak));
 EXPORT_SYMBOL(__bb_init_func);
-
-/*
- * This is defined (and referred to in profiling stub code) only by some GCC
- * versions in libgcov.
- *
- * Since SuSE backported the fix, we cannot handle it depending on GCC version.
- * So, unconditionally export it. But also give it a weak declaration, which
- * will be overridden by any other one.
- */
-
-extern void __gcov_init(void *) __attribute__((weak));
-EXPORT_SYMBOL(__gcov_init);
-
-extern void __gcov_merge_add(void *) __attribute__((weak));
-EXPORT_SYMBOL(__gcov_merge_add);

arch/x86/um/vdso/Makefile

@@ -46,8 +46,8 @@ $(vobjs): KBUILD_CFLAGS += $(CFL)
 #
 # vDSO code runs in userspace and -pg doesn't help with profiling anyway.
 #
-CFLAGS_REMOVE_vdso-note.o = -pg
-CFLAGS_REMOVE_um_vdso.o = -pg
+CFLAGS_REMOVE_vdso-note.o = -pg -fprofile-arcs -ftest-coverage
+CFLAGS_REMOVE_um_vdso.o = -pg -fprofile-arcs -ftest-coverage
 
 targets += vdso-syms.lds
 obj-$(VDSO64-y)			+= vdso-syms.lds