From 1f972505011c27d09423a46707789192a039b66a Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Thu, 21 Jun 2018 20:35:26 -0400 Subject: [PATCH] locking/qspinlock: Fix build for anonymous union in older GCC compilers [ Upstream commit 6cc65be4f6f2a7186af8f3e09900787c7912dad2 ] One of my tests compiles the kernel with gcc 4.5.3, and I hit the following build error: include/linux/semaphore.h: In function 'sema_init': include/linux/semaphore.h:35:17: error: unknown field 'val' specified in initializer include/linux/semaphore.h:35:17: warning: missing braces around initializer include/linux/semaphore.h:35:17: warning: (near initialization for '(anonymous).raw_lock..val') I bisected it down to: 625e88be1f41 ("locking/qspinlock: Merge 'struct __qspinlock' into 'struct qspinlock'") ... which makes qspinlock have an anonymous union, which makes initializing it special for older compilers. By adding strategic brackets, it makes the build happy again. Signed-off-by: Steven Rostedt (VMware) Acked-by: Waiman Long Cc: Andrew Morton Cc: Boqun Feng Cc: Linus Torvalds Cc: Peter Zijlstra (Intel) Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Fixes: 625e88be1f41 ("locking/qspinlock: Merge 'struct __qspinlock' into 'struct qspinlock'") Link: http://lkml.kernel.org/r/20180621203526.172ab5c4@vmware.local.home Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- include/asm-generic/qspinlock_types.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/asm-generic/qspinlock_types.h b/include/asm-generic/qspinlock_types.h index 0763f06..d10f1e7 100644 --- a/include/asm-generic/qspinlock_types.h +++ b/include/asm-generic/qspinlock_types.h @@ -63,7 +63,7 @@ typedef struct qspinlock { /* * Initializier */ -#define __ARCH_SPIN_LOCK_UNLOCKED { .val = ATOMIC_INIT(0) } +#define __ARCH_SPIN_LOCK_UNLOCKED { { .val = ATOMIC_INIT(0) } } /* * Bitfields in the atomic value: -- 2.7.4