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authorMauro Carvalho Chehab <mchehab@redhat.com>2012-04-19 09:23:28 -0300
committerMauro Carvalho Chehab <mchehab@redhat.com>2012-04-19 09:23:28 -0300
commitd5aeee8cb28317ef608ecac421abc4d986d585d2 (patch)
tree70ec8ed8891f26e5c58152ffca9924ea1c58fe3a /include/linux/bug.h
parent32898a145404acbebe3256709e012c2830a2043b (diff)
parente816b57a337ea3b755de72bec38c10c864f23015 (diff)
Merge tag 'v3.4-rc3' into staging/for_v3.5
* tag 'v3.4-rc3': (3755 commits) Linux 3.4-rc3 x86-32: fix up strncpy_from_user() sign error ARM: 7386/1: jump_label: fixup for rename to static_key ARM: 7384/1: ThumbEE: Disable userspace TEEHBR access for !CONFIG_ARM_THUMBEE ARM: 7382/1: mm: truncate memory banks to fit in 4GB space for classic MMU ARM: 7359/2: smp_twd: Only wait for reprogramming on active cpus PCI: Fix regression in pci_restore_state(), v3 SCSI: Fix error handling when no ULD is attached ARM: OMAP: clock: cleanup CPUfreq leftovers, fix build errors ARM: dts: remove blank interrupt-parent properties ARM: EXYNOS: Fix Kconfig dependencies for device tree enabled machine files do not export kernel's NULL #define to userspace ARM: EXYNOS: Remove broken config values for touchscren for NURI board ARM: EXYNOS: set fix xusbxti clock for NURI and Universal210 boards ARM: EXYNOS: fix regulator name for NURI board ARM: SAMSUNG: make SAMSUNG_PM_DEBUG select DEBUG_LL cpufreq: OMAP: fix build errors: depends on ARCH_OMAP2PLUS sparc64: Eliminate obsolete __handle_softirq() function sparc64: Fix bootup crash on sun4v. ARM: msm: Fix section mismatches in proc_comm.c ...
Diffstat (limited to 'include/linux/bug.h')
-rw-r--r--include/linux/bug.h61
1 files changed, 61 insertions, 0 deletions
diff --git a/include/linux/bug.h b/include/linux/bug.h
index d276b5510c83..72961c39576a 100644
--- a/include/linux/bug.h
+++ b/include/linux/bug.h
@@ -11,6 +11,67 @@ enum bug_trap_type {
struct pt_regs;
+#ifdef __CHECKER__
+#define BUILD_BUG_ON_NOT_POWER_OF_2(n)
+#define BUILD_BUG_ON_ZERO(e) (0)
+#define BUILD_BUG_ON_NULL(e) ((void*)0)
+#define BUILD_BUG_ON(condition)
+#define BUILD_BUG() (0)
+#else /* __CHECKER__ */
+
+/* Force a compilation error if a constant expression is not a power of 2 */
+#define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
+ BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
+
+/* Force a compilation error if condition is true, but also produce a
+ result (of value 0 and type size_t), so the expression can be used
+ e.g. in a structure initializer (or where-ever else comma expressions
+ aren't permitted). */
+#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
+#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
+
+/**
+ * BUILD_BUG_ON - break compile if a condition is true.
+ * @condition: the condition which the compiler should know is false.
+ *
+ * If you have some code which relies on certain constants being equal, or
+ * other compile-time-evaluated condition, you should use BUILD_BUG_ON to
+ * detect if someone changes it.
+ *
+ * The implementation uses gcc's reluctance to create a negative array, but
+ * gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
+ * to inline functions). So as a fallback we use the optimizer; if it can't
+ * prove the condition is false, it will cause a link error on the undefined
+ * "__build_bug_on_failed". This error message can be harder to track down
+ * though, hence the two different methods.
+ */
+#ifndef __OPTIMIZE__
+#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
+#else
+extern int __build_bug_on_failed;
+#define BUILD_BUG_ON(condition) \
+ do { \
+ ((void)sizeof(char[1 - 2*!!(condition)])); \
+ if (condition) __build_bug_on_failed = 1; \
+ } while(0)
+#endif
+
+/**
+ * BUILD_BUG - break compile if used.
+ *
+ * If you have some code that you expect the compiler to eliminate at
+ * build time, you should use BUILD_BUG to detect if it is
+ * unexpectedly used.
+ */
+#define BUILD_BUG() \
+ do { \
+ extern void __build_bug_failed(void) \
+ __linktime_error("BUILD_BUG failed"); \
+ __build_bug_failed(); \
+ } while (0)
+
+#endif /* __CHECKER__ */
+
#ifdef CONFIG_GENERIC_BUG
#include <asm-generic/bug.h>