[PATCH v5 2/5] xen/compiler: Replace opencoded __attribute__((noreturn))

[Andrew Cooper <andrew.cooper3@citrix.com>]

Make a formal define for noreturn in compiler.h, and fix up opencoded uses of
__attribute__((noreturn)).  This includes removing redundant uses with
function definitions which have a public declaration.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Keir Fraser <keir@xen.org>
Reviewed-by: Jan Beulich <JBeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Tim Deegan <tim@xen.org>
---
 xen/arch/arm/early_printk.c        |    2 +-
 xen/arch/x86/efi/boot.c            |    4 ++--
 xen/arch/x86/shutdown.c            |    2 +-
 xen/include/asm-arm/early_printk.h |    4 ++--
 xen/include/asm-x86/processor.h    |    2 +-
 xen/include/xen/compiler.h         |    2 ++
 xen/include/xen/lib.h              |    2 +-
 xen/include/xen/sched.h            |    4 ++--
 8 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/xen/arch/arm/early_printk.c b/xen/arch/arm/early_printk.c
index 41938bb..2870a30 100644
--- a/xen/arch/arm/early_printk.c
+++ b/xen/arch/arm/early_printk.c
@@ -52,7 +52,7 @@ void __init early_printk(const char *fmt, ...)
     va_end(args);
 }
 
-void __attribute__((noreturn)) __init
+void __init
 early_panic(const char *fmt, ...)
 {
     va_list args;
diff --git a/xen/arch/x86/efi/boot.c b/xen/arch/x86/efi/boot.c
index 0dd935c..a26e0af 100644
--- a/xen/arch/x86/efi/boot.c
+++ b/xen/arch/x86/efi/boot.c
@@ -183,7 +183,7 @@ static bool_t __init match_guid(const EFI_GUID *guid1, const EFI_GUID *guid2)
            !memcmp(guid1->Data4, guid2->Data4, sizeof(guid1->Data4));
 }
 
-static void __init __attribute__((__noreturn__)) blexit(const CHAR16 *str)
+static void __init noreturn blexit(const CHAR16 *str)
 {
     if ( str )
         PrintStr((CHAR16 *)str);
@@ -762,7 +762,7 @@ static void __init relocate_trampoline(unsigned long phys)
         *(u16 *)(*trampoline_ptr + (long)trampoline_ptr) = phys >> 4;
 }
 
-void EFIAPI __init __attribute__((__noreturn__))
+void EFIAPI __init noreturn
 efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable)
 {
     static EFI_GUID __initdata loaded_image_guid = LOADED_IMAGE_PROTOCOL;
diff --git a/xen/arch/x86/shutdown.c b/xen/arch/x86/shutdown.c
index 6eba271..6143c40 100644
--- a/xen/arch/x86/shutdown.c
+++ b/xen/arch/x86/shutdown.c
@@ -85,7 +85,7 @@ static inline void kb_wait(void)
             break;
 }
 
-static void __attribute__((noreturn)) __machine_halt(void *unused)
+static void noreturn __machine_halt(void *unused)
 {
     local_irq_disable();
     for ( ; ; )
diff --git a/xen/include/asm-arm/early_printk.h b/xen/include/asm-arm/early_printk.h
index 707bbf7..8047141 100644
--- a/xen/include/asm-arm/early_printk.h
+++ b/xen/include/asm-arm/early_printk.h
@@ -26,7 +26,7 @@
 
 void early_printk(const char *fmt, ...)
     __attribute__((format (printf, 1, 2)));
-void early_panic(const char *fmt, ...) __attribute__((noreturn))
+void noreturn early_panic(const char *fmt, ...)
     __attribute__((format (printf, 1, 2)));
 
 #else
@@ -35,7 +35,7 @@ static inline  __attribute__((format (printf, 1, 2))) void
 early_printk(const char *fmt, ...)
 {}
 
-static inline void  __attribute__((noreturn))
+static inline void noreturn
 __attribute__((format (printf, 1, 2))) early_panic(const char *fmt, ...)
 {while(1);}
 
diff --git a/xen/include/asm-x86/processor.h b/xen/include/asm-x86/processor.h
index 4629b32..4da545e 100644
--- a/xen/include/asm-x86/processor.h
+++ b/xen/include/asm-x86/processor.h
@@ -550,7 +550,7 @@ DECLARE_TRAP_HANDLER(spurious_interrupt_bug);
 
 void trap_nop(void);
 void enable_nmis(void);
-void __attribute__((noreturn)) do_nmi_crash(struct cpu_user_regs *regs);
+void noreturn do_nmi_crash(struct cpu_user_regs *regs);
 
 void syscall_enter(void);
 void sysenter_entry(void);
diff --git a/xen/include/xen/compiler.h b/xen/include/xen/compiler.h
index 7d6805c..c80398d 100644
--- a/xen/include/xen/compiler.h
+++ b/xen/include/xen/compiler.h
@@ -14,6 +14,8 @@
 #define always_inline __inline__ __attribute__ ((always_inline))
 #define noinline      __attribute__((noinline))
 
+#define noreturn      __attribute__((noreturn))
+
 #if (!defined(__clang__) && (__GNUC__ == 4) && (__GNUC_MINOR__ < 5))
 #define unreachable() do {} while (1)
 #else
diff --git a/xen/include/xen/lib.h b/xen/include/xen/lib.h
index 5b258fd..0d1a5d3 100644
--- a/xen/include/xen/lib.h
+++ b/xen/include/xen/lib.h
@@ -8,7 +8,7 @@
 #include <xen/string.h>
 #include <asm/bug.h>
 
-void __bug(char *file, int line) __attribute__((noreturn));
+void noreturn __bug(char *file, int line);
 void __warn(char *file, int line);
 
 #define BUG_ON(p)  do { if (unlikely(p)) BUG();  } while (0)
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index fb8bd36..00f0eba 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -580,7 +580,7 @@ void __domain_crash(struct domain *d);
  * Mark current domain as crashed and synchronously deschedule from the local
  * processor. This function never returns.
  */
-void __domain_crash_synchronous(void) __attribute__((noreturn));
+void noreturn __domain_crash_synchronous(void);
 #define domain_crash_synchronous() do {                                   \
     printk("domain_crash_sync called from %s:%d\n", __FILE__, __LINE__);  \
     __domain_crash_synchronous();                                         \
@@ -591,7 +591,7 @@ void __domain_crash_synchronous(void) __attribute__((noreturn));
  * the crash occured.  If addr is 0, look up address from last extable
  * redirection.
  */
-void asm_domain_crash_synchronous(unsigned long addr) __attribute__((noreturn));
+void noreturn asm_domain_crash_synchronous(unsigned long addr);
 
 #define set_current_state(_s) do { current->state = (_s); } while (0)
 void scheduler_init(void);
-- 
1.7.10.4