[profile] gcov_mutex must be static

Summary: Forget static keyword for gcov_mutex in https://reviews.llvm.org/D74953 and that causes test failure on mac.

Reviewers: erik.pilkington, vsk

Reviewed By: vsk

Subscribers: vsk, dexonsmith, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D75080

Author: calixteman

compiler-rt/lib/profile/GCDAProfiling.c

@@ -67,12 +67,12 @@ typedef unsigned long long uint64_t;
 
 #ifndef _WIN32
 #include <pthread.h>
-pthread_mutex_t gcov_mutex = PTHREAD_MUTEX_INITIALIZER;
+static pthread_mutex_t gcov_mutex = PTHREAD_MUTEX_INITIALIZER;
 static __inline void gcov_lock() { pthread_mutex_lock(&gcov_mutex); }
 static __inline void gcov_unlock() { pthread_mutex_unlock(&gcov_mutex); }
 #else
 #include <windows.h>
-SRWLOCK gcov_mutex = SRWLOCK_INIT;
+static SRWLOCK gcov_mutex = SRWLOCK_INIT;
 static __inline void gcov_lock() { AcquireSRWLockExclusive(&gcov_mutex); }
 static __inline void gcov_unlock() { ReleaseSRWLockExclusive(&gcov_mutex); }
 #endif