tests/test-ignore-value.c

   1 /* Test the "ignore-value" module.
   2
   3    Copyright (C) 2011-2018 Free Software Foundation, Inc.
   4
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program 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 General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 /* Written by Eric Blake.  */
  19
  20 #include <config.h>
  21
  22 #include "ignore-value.h"
  23
  24 #include <stdio.h>
  25
  26 #ifndef _GL_ATTRIBUTE_RETURN_CHECK
  27 # if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 4)
  28 #  define _GL_ATTRIBUTE_RETURN_CHECK
  29 # else
  30 #  define _GL_ATTRIBUTE_RETURN_CHECK __attribute__((__warn_unused_result__))
  31 # endif
  32 #endif
  33
  34 struct s { int i; };
  35 static char doChar (void) _GL_ATTRIBUTE_RETURN_CHECK;
  36 static int doInt (void) _GL_ATTRIBUTE_RETURN_CHECK;
  37 static off_t doOff (void) _GL_ATTRIBUTE_RETURN_CHECK;
  38 static void *doPtr (void) _GL_ATTRIBUTE_RETURN_CHECK;
  39 static struct s doStruct (void) _GL_ATTRIBUTE_RETURN_CHECK;
  40
  41 static char
  42 doChar (void)
  43 {
  44   return 0;
  45 }
  46
  47 static int
  48 doInt (void)
  49 {
  50   return 0;
  51 }
  52
  53 static off_t
  54 doOff (void)
  55 {
  56   return 0;
  57 }
  58
  59 static void *
  60 doPtr (void)
  61 {
  62   return NULL;
  63 }
  64
  65 static struct s
  66 doStruct (void)
  67 {
  68   static struct s s1;
  69   return s1;
  70 }
  71
  72 int
  73 main (void)
  74 {
  75   /* If this test can compile with -Werror and the same warnings as
  76      the rest of the project, then we are properly silencing warnings
  77      about ignored return values.  */
  78   ignore_value (doChar ());
  79   ignore_value (doInt ());
  80   ignore_value (doOff ());
  81   ignore_value (doPtr ());
  82   ignore_value (doStruct ());
  83   return 0;
  84 }