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Fix undefined behaviour. * lib/bitrotate.h (rotl16, rotr16, rotl8, rotr8): Case x to 'unsigned int', to avoid shift operations on 'int'. * lib/xmemdup0.c (xmemdup0): Don't invoke memcpy with a zero size. * tests/test-count-leading-zeros.c (main): Use a random number that has as many bits as TYPE, not only 2*15 or 2*31 bits. * tests/test-count-trailing-zeros.c (main): Likewise. * tests/test-count-one-bits.c (main): Likewise. * tests/test-memmem.c: Don't include "null-ptr.h". (main): Use zerosize_ptr() instead of null_ptr(). * modules/memmem-tests (Files): Remove tests/null-ptr.h.
author Bruno Haible <bruno@clisp.org>
date Sat, 09 Mar 2019 20:32:25 +0100
parents b06060465f09
children
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dnl Check whether limits.h has needed features.

dnl Copyright 2016-2019 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

dnl From Paul Eggert.

AC_DEFUN_ONCE([gl_LIMITS_H],
[
  gl_CHECK_NEXT_HEADERS([limits.h])

  AC_CACHE_CHECK([whether limits.h has LLONG_MAX, WORD_BIT, ULLONG_WIDTH etc.],
    [gl_cv_header_limits_width],
    [AC_COMPILE_IFELSE(
       [AC_LANG_PROGRAM(
          [[#ifndef __STDC_WANT_IEC_60559_BFP_EXT__
             #define __STDC_WANT_IEC_60559_BFP_EXT__ 1
            #endif
            #include <limits.h>
            long long llm = LLONG_MAX;
            int wb = WORD_BIT;
            int ullw = ULLONG_WIDTH;
          ]])],
       [gl_cv_header_limits_width=yes],
       [gl_cv_header_limits_width=no])])
  if test "$gl_cv_header_limits_width" = yes; then
    LIMITS_H=
  else
    LIMITS_H=limits.h
  fi
  AC_SUBST([LIMITS_H])
  AM_CONDITIONAL([GL_GENERATE_LIMITS_H], [test -n "$LIMITS_H"])
])

dnl Unconditionally enables the replacement of <limits.h>.
AC_DEFUN([gl_REPLACE_LIMITS_H],
[
  AC_REQUIRE([gl_LIMITS_H])
  LIMITS_H='limits.h'
  AM_CONDITIONAL([GL_GENERATE_LIMITS_H], [test -n "$LIMITS_H"])
])