Re: lib/49989: libc++ fails to build with g++ 5.1 due to libpthread volatiles

[christos%zoulas.com@localhost (Christos Zoulas)]

On Jun 20,  3:05pm, pooka%iki.fi@localhost (pooka%iki.fi@localhost) wrote:
-- Subject: lib/49989: libc++ fails to build with g++ 5.1 due to libpthread v

Index: pthread_types.h
===================================================================
RCS file: /cvsroot/src/lib/libpthread/pthread_types.h,v
retrieving revision 1.13
diff -u -u -r1.13 pthread_types.h
--- pthread_types.h	2 Aug 2008 19:46:30 -0000	1.13
+++ pthread_types.h	20 Jun 2015 16:03:04 -0000
@@ -84,6 +84,23 @@
 };
 
 /*
+ * libc++ expects to be using PTHREAD_MUTEX_INITIALIZER as a member
+ * initializer. This does not work for volatile types. Since c++
+ * does not touch the guts of those types, we redefine them as non-volatile
+ */
+#ifdef __cplusplus
+# ifdef __CPU_SIMPLE_LOCK_PAD
+#  define __pthread_mutex_spin_t unsigned char
+# else
+#  define __pthread_mutex_spin_t unsigned int
+# endif
+# define __pthread_mutex_volatile
+#else
+# define __pthread_mutex_spin_t pthread_spin_t
+# define __pthread_mutex_volatile volatile
+#endif
+
+/*
  * ptm_owner is the actual lock field which is locked via CAS operation.
  * This structure's layout is designed to compatible with the previous
  * version used in SA pthreads.
@@ -100,16 +117,16 @@
 #endif
 struct	__pthread_mutex_st {
 	unsigned int	ptm_magic;
-	pthread_spin_t	ptm_errorcheck;
+	__pthread_mutex_spin_t	ptm_errorcheck;
 #ifdef __CPU_SIMPLE_LOCK_PAD
 	uint8_t		ptm_pad1[3];
 #endif
-	pthread_spin_t	ptm_interlock;	/* unused - backwards compat */
+	__pthread_mutex_spin_t	ptm_interlock;	/* unused - backwards compat */
 #ifdef __CPU_SIMPLE_LOCK_PAD
 	uint8_t		ptm_pad2[3];
 #endif
-	volatile pthread_t ptm_owner;
-	pthread_t * volatile ptm_waiters;
+	__pthread_mutex_volatile pthread_t ptm_owner;
+	pthread_t * __pthread_mutex_volatile ptm_waiters;
 	unsigned int	ptm_recursed;
 	void		*ptm_spare2;	/* unused - backwards compat */
 };