1 files changed, 118 insertions, 0 deletions
diff --git a/gnulib_m4/stdbool.m4 b/gnulib_m4/stdbool.m4
new file mode 100644
index 0000000..d4d54d0
--- /dev/null
+++ b/gnulib_m4/stdbool.m4
@@ -0,0 +1,118 @@
+# Check for stdbool.h that conforms to C99.
+
+dnl Copyright (C) 2002-2006, 2009-2023 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.
+
+#serial 10
+
+# Prepare for substituting <stdbool.h> if it is not supported.
+
+AC_DEFUN([gl_STDBOOL_H],
+[
+  AC_REQUIRE([AC_CHECK_HEADER_STDBOOL])
+  AC_REQUIRE([AC_CANONICAL_HOST])
+
+  dnl On some platforms, <stdbool.h> does not exist or does not conform to C99.
+  dnl On Solaris 10 with CC=cc CXX=CC, <stdbool.h> exists but is not usable
+  dnl in C++ mode (and no <cstdbool> exists). In this case, we use our
+  dnl replacement, also in C mode (for binary compatibility between C and C++).
+  if test "$ac_cv_header_stdbool_h" = yes; then
+    case "$host_os" in
+      solaris*)
+        if test -z "$GCC"; then
+          GL_GENERATE_STDBOOL_H=true
+        else
+          GL_GENERATE_STDBOOL_H=false
+        fi
+        ;;
+      *)
+        GL_GENERATE_STDBOOL_H=false
+        ;;
+    esac
+  else
+    GL_GENERATE_STDBOOL_H=true
+  fi
+
+  if test "$ac_cv_type__Bool" = yes; then
+    HAVE__BOOL=1
+  else
+    HAVE__BOOL=0
+  fi
+  AC_SUBST([HAVE__BOOL])
+])
+
+m4_version_prereq([2.72], [], [
+
+AC_DEFUN([AC_CHECK_HEADER_STDBOOL],
+  [AC_CHECK_TYPES([_Bool])
+   AC_CACHE_CHECK([for stdbool.h that conforms to C99 or later],
+     [ac_cv_header_stdbool_h],
+     [AC_COMPILE_IFELSE(
+        [AC_LANG_PROGRAM(
+           [[#include <stdbool.h>
+
+             /* "true" and "false" should be usable in #if expressions and
+                integer constant expressions, and "bool" should be a valid
+                type name.
+
+                Although C99 requires bool, true, and false to be macros,
+                C23 and C++11 overrule that, so do not test for that.
+                Although C99 requires __bool_true_false_are_defined and
+                _Bool, C23 says they are obsolescent, so do not require
+                them.  */
+
+             #if !true
+               #error "'true' is not true"
+             #endif
+             #if true != 1
+               #error "'true' is not equal to 1"
+             #endif
+             char b[true == 1 ? 1 : -1];
+             char c[true];
+
+             #if false
+               #error "'false' is not false"
+             #endif
+             #if false != 0
+               #error "'false' is not equal to 0"
+             #endif
+             char d[false == 0 ? 1 : -1];
+
+             enum { e = false, f = true, g = false * true, h = true * 256 };
+
+             char i[(bool) 0.5 == true ? 1 : -1];
+             char j[(bool) 0.0 == false ? 1 : -1];
+             char k[sizeof (bool) > 0 ? 1 : -1];
+
+             struct sb { bool s: 1; bool t; } s;
+             char l[sizeof s.t > 0 ? 1 : -1];
+
+             /* The following fails for
+                HP aC++/ANSI C B3910B A.05.55 [Dec 04 2003]. */
+             bool m[h];
+             char n[sizeof m == h * sizeof m[0] ? 1 : -1];
+             char o[-1 - (bool) 0 < 0 ? 1 : -1];
+             /* Catch a bug in an HP-UX C compiler.  See
+                https://gcc.gnu.org/ml/gcc-patches/2003-12/msg02303.html
+                https://lists.gnu.org/r/bug-coreutils/2005-11/msg00161.html
+              */
+             bool p = true;
+             bool *pp = &p;
+           ]],
+           [[
+             bool ps = &s;
+             *pp |= p;
+             *pp |= ! p;
+
+             /* Refer to every declared value, so they cannot be
+                discarded as unused.  */
+             return (!b + !c + !d + !e + !f + !g + !h + !i + !j + !k
+                     + !l + !m + !n + !o + !p + !pp + !ps);
+           ]])],
+        [ac_cv_header_stdbool_h=yes],
+        [ac_cv_header_stdbool_h=no])])
+])# AC_CHECK_HEADER_STDBOOL
+
+]) # m4_version_prereq 2.72