[Google gcc-4_8] always emit __gcov_get_profile_prefix when linking libgcov.a

[Rong Xu]

Hi,

This patch is for google/gcc-4_8 branch. It fixes a regression in
earlier libgcov refactoring.

Thanks,

-Rong

2014-01-23  Rong Xu  <x...@google.com>

        * libgcov-driver.c (__gcov_get_profile_prefix): Always emit
        this function.

Index: libgcov-driver.c
===================================================================
--- libgcov-driver.c    (revision 206736)
+++ libgcov-driver.c    (working copy)
@@ -68,6 +68,8 @@ extern struct gcov_info *get_gcov_list (void) ATTR
    these symbols will always need to be resolved.  */
 void (*__gcov_dummy_ref1)(void) = &__gcov_reset;
 void (*__gcov_dummy_ref2)(void) = &__gcov_dump;
+extern char *__gcov_get_profile_prefix (void);
+char *(*__gcov_dummy_ref3)(void) = &__gcov_get_profile_prefix;

 /* Default callback function for profile instrumentation callback.  */
 extern void __coverage_callback (gcov_type, int);