summaryrefslogtreecommitdiff
path: root/include/linux/bug.h
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2013-02-21 17:38:49 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-21 17:38:49 -0800
commit7c2db36e730ee4facd341679ecb21ee73ba92831 (patch)
tree75016fba72aaf0581b9263f7fa4c565e6e634f3c /include/linux/bug.h
parent8b5628ab83b671f96ac9f174c1bd51c92589fc82 (diff)
parenta47a376f1c025e23e836c0376813c0424de665c2 (diff)
Merge branch 'akpm' (incoming from Andrew)
Merge misc patches from Andrew Morton: - Florian has vanished so I appear to have become fbdev maintainer again :( - Joel and Mark are distracted to welcome to the new OCFS2 maintainer - The backlight queue - Small core kernel changes - lib/ updates - The rtc queue - Various random bits * akpm: (164 commits) rtc: rtc-davinci: use devm_*() functions rtc: rtc-max8997: use devm_request_threaded_irq() rtc: rtc-max8907: use devm_request_threaded_irq() rtc: rtc-da9052: use devm_request_threaded_irq() rtc: rtc-wm831x: use devm_request_threaded_irq() rtc: rtc-tps80031: use devm_request_threaded_irq() rtc: rtc-lp8788: use devm_request_threaded_irq() rtc: rtc-coh901331: use devm_clk_get() rtc: rtc-vt8500: use devm_*() functions rtc: rtc-tps6586x: use devm_request_threaded_irq() rtc: rtc-imxdi: use devm_clk_get() rtc: rtc-cmos: use dev_warn()/dev_dbg() instead of printk()/pr_debug() rtc: rtc-pcf8583: use dev_warn() instead of printk() rtc: rtc-sun4v: use pr_warn() instead of printk() rtc: rtc-vr41xx: use dev_info() instead of printk() rtc: rtc-rs5c313: use pr_err() instead of printk() rtc: rtc-at91rm9200: use dev_dbg()/dev_err() instead of printk()/pr_debug() rtc: rtc-rs5c372: use dev_dbg()/dev_warn() instead of printk()/pr_debug() rtc: rtc-ds2404: use dev_err() instead of printk() rtc: rtc-efi: use dev_err()/dev_warn()/pr_err() instead of printk() ...
Diffstat (limited to 'include/linux/bug.h')
-rw-r--r--include/linux/bug.h47
1 files changed, 26 insertions, 21 deletions
diff --git a/include/linux/bug.h b/include/linux/bug.h
index b1cf40de847e..7f4818673c41 100644
--- a/include/linux/bug.h
+++ b/include/linux/bug.h
@@ -2,6 +2,7 @@
#define _LINUX_BUG_H
#include <asm/bug.h>
+#include <linux/compiler.h>
enum bug_trap_type {
BUG_TRAP_TYPE_NONE = 0,
@@ -12,11 +13,12 @@ enum bug_trap_type {
struct pt_regs;
#ifdef __CHECKER__
-#define BUILD_BUG_ON_NOT_POWER_OF_2(n)
+#define BUILD_BUG_ON_NOT_POWER_OF_2(n) (0)
#define BUILD_BUG_ON_ZERO(e) (0)
#define BUILD_BUG_ON_NULL(e) ((void*)0)
#define BUILD_BUG_ON_INVALID(e) (0)
-#define BUILD_BUG_ON(condition)
+#define BUILD_BUG_ON_MSG(cond, msg) (0)
+#define BUILD_BUG_ON(condition) (0)
#define BUILD_BUG() (0)
#else /* __CHECKER__ */
@@ -39,29 +41,37 @@ struct pt_regs;
#define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e))))
/**
+ * BUILD_BUG_ON_MSG - break compile if a condition is true & emit supplied
+ * error message.
+ * @condition: the condition which the compiler should know is false.
+ *
+ * See BUILD_BUG_ON for description.
+ */
+#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
+
+/**
* 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
+ * some 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.
+ * The implementation uses gcc's reluctance to create a negative array, but gcc
+ * (as of 4.4) only emits that error for obvious cases (e.g. not arguments to
+ * inline functions). Luckily, in 4.3 they added the "error" function
+ * attribute just for this type of case. Thus, we use a negative sized array
+ * (should always create an error on gcc versions older than 4.4) and then call
+ * an undefined function with the error attribute (should always create an
+ * error on gcc 4.3 and later). If for some reason, neither creates a
+ * compile-time error, we'll still have a link-time error, which is harder to
+ * track down.
*/
#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)
+#define BUILD_BUG_ON(condition) \
+ BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
#endif
/**
@@ -71,12 +81,7 @@ extern int __build_bug_on_failed;
* 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)
+#define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed")
#endif /* __CHECKER__ */