lib/assure.h

   1 /* Run-time assert-like macros.
   2
   3    Copyright (C) 2014-2024 Free Software Foundation, Inc.
   4
   5    This file is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU Lesser General Public License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    License, or (at your option) any later version.
   9
  10    This file is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 /* Written by Paul Eggert.  */
  19
  20 #ifndef _GL_ASSURE_H
  21 #define _GL_ASSURE_H
  22
  23 #include <assert.h>
  24 #include "verify.h"
  25
  26 /* Evaluate an assertion E that is guaranteed to be true.
  27    If NDEBUG is not defined, abort the program if E is false.
  28    If NDEBUG is defined, the compiler can assume E and behavior is
  29    undefined if E is false, fails to evaluate, or has side effects.
  30
  31    Unlike standard 'assert', this macro evaluates E even when NDEBUG
  32    is defined, so as to catch typos, avoid some GCC warnings, and
  33    improve performance when E is simple enough.
  34
  35    Also see the documentation for 'assume' in verify.h.  */
  36
  37 #ifdef NDEBUG
  38 # define affirm(E) assume (E)
  39 #else
  40 # define affirm(E) assert (E)
  41 #endif
  42
  43 /* Check E's value at runtime, and report an error and abort if not.
  44    However, do nothing if NDEBUG is defined.
  45
  46    Unlike standard 'assert', this macro compiles E even when NDEBUG
  47    is defined, so as to catch typos and avoid some GCC warnings.
  48    Unlike 'affirm', it is OK for E to use hard-to-optimize features,
  49    since E is not executed if NDEBUG is defined.  */
  50
  51 #ifdef NDEBUG
  52 # define assure(E) ((void) (0 && (E)))
  53 #else
  54 # define assure(E) assert (E)
  55 #endif
  56
  57 #endif