Back out Bug 1127201 (part 3) for various problems.

xpcom/glue/nsDebug.h

@@ -49,6 +49,33 @@ inline bool NS_warn_if_impl(bool aCondition, const char* aExpr,
 #endif
 #endif
 
+/**
+ * Abort the execution of the program if the expression evaluates to
+ * false.
+ *
+ * There is no status value returned from the macro.
+ *
+ * Note that the non-debug version of this macro does <b>not</b>
+ * evaluate the expression argument. Hence side effect statements
+ * as arguments to the macro will yield improper execution in a
+ * non-debug build. For example:
+ *
+ *      NS_ABORT_IF_FALSE(0 == foo++, "yikes foo should be zero");
+ *
+ * Note also that the non-debug version of this macro does <b>not</b>
+ * evaluate the message argument.
+ */
+#ifdef DEBUG
+#define NS_ABORT_IF_FALSE(_expr, _msg)                        \
+  do {                                                        \
+    if (!(_expr)) {                                           \
+      NS_DebugBreak(NS_DEBUG_ABORT, _msg, #_expr, __FILE__, __LINE__); \
+    }                                                         \
+  } while(0)
+#else
+#define NS_ABORT_IF_FALSE(_expr, _msg) do { /* nothing */ } while(0)
+#endif
+
 /**
  * Warn if a given condition is false.
  *