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authorColin Watson <cjwatson@debian.org>2020-06-01 18:06:29 +0100
committerColin Watson <cjwatson@debian.org>2020-06-01 18:06:29 +0100
commit3cb95d6411ace1f422db912a7a019511899b0e3f (patch)
treee6bbe1f936ebeb1462b4a3efdaba305ba3e7000b /gl/lib/assure.h
parentea9974fa9eea80f19126edbd7e132186d153d2b2 (diff)
parentf0621ef0556b55ece404ea57808f0e3773c5dc64 (diff)
Import man-db_2.9.2.orig.tar.xz
Diffstat (limited to 'gl/lib/assure.h')
-rw-r--r--gl/lib/assure.h24
1 files changed, 22 insertions, 2 deletions
diff --git a/gl/lib/assure.h b/gl/lib/assure.h
index 8ea2f6e4..09a4edfa 100644
--- a/gl/lib/assure.h
+++ b/gl/lib/assure.h
@@ -21,12 +21,32 @@
#define _GL_ASSURE_H
#include <assert.h>
+#include "verify.h"
+
+/* Evaluate an assertion E that is guaranteed to be true.
+ If NDEBUG is not defined, abort the program if E is false.
+ If NDEBUG is defined, the compiler can assume E and behavior is
+ undefined if E is false, fails to evaluate, or has side effects.
+
+ Unlike standard 'assert', this macro evaluates E even when NDEBUG
+ is defined, so as to catch typos, avoid some GCC warnings, and
+ improve performance when E is simple enough.
+
+ Also see the documentation for 'assume' in verify.h. */
+
+#ifdef NDEBUG
+# define affirm(E) assume (E)
+#else
+# define affirm(E) assert (E)
+#endif
/* Check E's value at runtime, and report an error and abort if not.
However, do nothing if NDEBUG is defined.
- Unlike standard 'assert', this macro always compiles E even when NDEBUG
- is defined, so as to catch typos and avoid some GCC warnings. */
+ Unlike standard 'assert', this macro compiles E even when NDEBUG
+ is defined, so as to catch typos and avoid some GCC warnings.
+ Unlike 'affirm', it is OK for E to use hard-to-optimize features,
+ since E is not executed if NDEBUG is defined. */
#ifdef NDEBUG
# define assure(E) ((void) (0 && (E)))