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Enhance setuid-tunables test
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Instead of passing GLIBC_TUNABLES via the environment, pass the
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environment variable from parent to child.  This allows us to test
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multiple variables to ensure better coverage.
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The test list currently only includes the case that's already being
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tested.  More tests will be added later.
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Reviewed-by: Carlos O'Donell <carlos@redhat.com>
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(cherry picked from commit 061fe3f8add46a89b7453e87eabb9c4695005ced)
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Also add intprops.h from 2.29 from commit 8e6fd2bdb21efe2cc1ae7571ff8fb2599db6a05a
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diff --git a/elf/Makefile b/elf/Makefile
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index fc9c685b9d23bb6c..2093cefa7e73349e 100644
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--- a/elf/Makefile
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+++ b/elf/Makefile
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@@ -1597,8 +1597,6 @@ $(objpfx)tst-nodelete-dlclose.out: $(objpfx)tst-nodelete-dlclose-dso.so \
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 tst-env-setuid-ENV = MALLOC_CHECK_=2 MALLOC_MMAP_THRESHOLD_=4096 \
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 		     LD_HWCAP_MASK=0x1
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-tst-env-setuid-tunables-ENV = \
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-	GLIBC_TUNABLES=glibc.malloc.check=2:glibc.malloc.mmap_threshold=4096
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 $(objpfx)tst-debug1: $(libdl)
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 $(objpfx)tst-debug1.out: $(objpfx)tst-debug1mod1.so
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diff --git a/elf/tst-env-setuid-tunables.c b/elf/tst-env-setuid-tunables.c
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index d7c4f0d5742cd526..a48281b175af6920 100644
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--- a/elf/tst-env-setuid-tunables.c
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+++ b/elf/tst-env-setuid-tunables.c
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@@ -25,35 +25,50 @@
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 #include "config.h"
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 #undef _LIBC
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-#define test_parent test_parent_tunables
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-#define test_child test_child_tunables
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-
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-static int test_child_tunables (void);
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-static int test_parent_tunables (void);
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-
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-#include "tst-env-setuid.c"
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+#include <errno.h>
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+#include <fcntl.h>
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+#include <stdlib.h>
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+#include <stdint.h>
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+#include <stdio.h>
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+#include <string.h>
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+#include <sys/stat.h>
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+#include <sys/wait.h>
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+#include <unistd.h>
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+#include <intprops.h>
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+#include <array_length.h>
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+
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+#include <support/check.h>
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+#include <support/support.h>
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+#include <support/test-driver.h>
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+#include <support/capture_subprocess.h>
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+
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+const char *teststrings[] =
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+{
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+  "glibc.malloc.check=2:glibc.malloc.mmap_threshold=4096",
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+};
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-#define CHILD_VALSTRING_VALUE "glibc.malloc.mmap_threshold=4096"
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-#define PARENT_VALSTRING_VALUE \
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-  "glibc.malloc.check=2:glibc.malloc.mmap_threshold=4096"
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+const char *resultstrings[] =
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+{
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+  "glibc.malloc.mmap_threshold=4096",
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+};
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 static int
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-test_child_tunables (void)
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+test_child (int off)
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 {
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   const char *val = getenv ("GLIBC_TUNABLES");
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 #if HAVE_TUNABLES
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-  if (val != NULL && strcmp (val, CHILD_VALSTRING_VALUE) == 0)
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+  if (val != NULL && strcmp (val, resultstrings[off]) == 0)
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     return 0;
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   if (val != NULL)
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-    printf ("Unexpected GLIBC_TUNABLES VALUE %s\n", val);
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+    printf ("[%d] Unexpected GLIBC_TUNABLES VALUE %s\n", off, val);
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   return 1;
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 #else
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   if (val != NULL)
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     {
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-      printf ("GLIBC_TUNABLES not cleared\n");
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+      printf ("[%d] GLIBC_TUNABLES not cleared\n", off);
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       return 1;
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     }
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   return 0;
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@@ -61,15 +76,48 @@ test_child_tunables (void)
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 }
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 static int
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-test_parent_tunables (void)
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+do_test (int argc, char **argv)
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 {
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-  const char *val = getenv ("GLIBC_TUNABLES");
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+  /* Setgid child process.  */
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+  if (argc == 2)
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+    {
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+      if (getgid () == getegid ())
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+	/* This can happen if the file system is mounted nosuid.  */
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+	FAIL_UNSUPPORTED ("SGID failed: GID and EGID match (%jd)\n",
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+			  (intmax_t) getgid ());
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-  if (val != NULL && strcmp (val, PARENT_VALSTRING_VALUE) == 0)
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-    return 0;
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+      int ret = test_child (atoi (argv[1]));
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-  if (val != NULL)
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-    printf ("Unexpected GLIBC_TUNABLES VALUE %s\n", val);
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+      if (ret != 0)
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+	exit (1);
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-  return 1;
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+      exit (EXIT_SUCCESS);
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+    }
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+  else
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+    {
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+      int ret = 0;
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+
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+      /* Spawn tests.  */
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+      for (int i = 0; i < array_length (teststrings); i++)
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+	{
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+	  char buf[INT_BUFSIZE_BOUND (int)];
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+
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+	  printf ("Spawned test for %s (%d)\n", teststrings[i], i);
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+	  snprintf (buf, sizeof (buf), "%d\n", i);
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+	  if (setenv ("GLIBC_TUNABLES", teststrings[i], 1) != 0)
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+	    exit (1);
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+
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+	  int status = support_capture_subprogram_self_sgid (buf);
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+
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+	  /* Bail out early if unsupported.  */
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+	  if (WEXITSTATUS (status) == EXIT_UNSUPPORTED)
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+	    return EXIT_UNSUPPORTED;
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+
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+	  ret |= status;
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+	}
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+      return ret;
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+    }
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 }
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+
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+#define TEST_FUNCTION_ARGV do_test
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+#include <support/test-driver.c>
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diff --git a/include/intprops.h b/include/intprops.h
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new file mode 100644
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index 0000000000000000..9702aec4c6e3c80a
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--- /dev/null
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+++ b/include/intprops.h
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@@ -0,0 +1,455 @@
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+/* intprops.h -- properties of integer types
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+
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+   Copyright (C) 2001-2018 Free Software Foundation, Inc.
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+
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+   This program is free software: you can redistribute it and/or modify it
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+   under the terms of the GNU Lesser General Public License as published
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+   by the Free Software Foundation; either version 2.1 of the License, or
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+   (at your option) any later version.
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+
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+   This program is distributed in the hope that it will be useful,
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+   but WITHOUT ANY WARRANTY; without even the implied warranty of
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+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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+   GNU Lesser General Public License for more details.
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+
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+   You should have received a copy of the GNU Lesser General Public License
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+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
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+
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+/* Written by Paul Eggert.  */
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+
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+#ifndef _GL_INTPROPS_H
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+#define _GL_INTPROPS_H
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+
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+#include <limits.h>
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+
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+/* Return a value with the common real type of E and V and the value of V.
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+   Do not evaluate E.  */
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+#define _GL_INT_CONVERT(e, v) ((1 ? 0 : (e)) + (v))
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+
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+/* Act like _GL_INT_CONVERT (E, -V) but work around a bug in IRIX 6.5 cc; see
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+   <https://lists.gnu.org/r/bug-gnulib/2011-05/msg00406.html>.  */
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+#define _GL_INT_NEGATE_CONVERT(e, v) ((1 ? 0 : (e)) - (v))
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+
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+/* The extra casts in the following macros work around compiler bugs,
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+   e.g., in Cray C 5.0.3.0.  */
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+
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+/* True if the arithmetic type T is an integer type.  bool counts as
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+   an integer.  */
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+#define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
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+
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+/* True if the real type T is signed.  */
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+#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
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+
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+/* Return 1 if the real expression E, after promotion, has a
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+   signed or floating type.  Do not evaluate E.  */
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+#define EXPR_SIGNED(e) (_GL_INT_NEGATE_CONVERT (e, 1) < 0)
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+
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+
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+/* Minimum and maximum values for integer types and expressions.  */
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+
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+/* The width in bits of the integer type or expression T.
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+   Do not evaluate T.
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+   Padding bits are not supported; this is checked at compile-time below.  */
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+#define TYPE_WIDTH(t) (sizeof (t) * CHAR_BIT)
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+
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+/* The maximum and minimum values for the integer type T.  */
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+#define TYPE_MINIMUM(t) ((t) ~ TYPE_MAXIMUM (t))
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+#define TYPE_MAXIMUM(t)                                                 \
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+  ((t) (! TYPE_SIGNED (t)                                               \
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+        ? (t) -1                                                        \
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+        : ((((t) 1 << (TYPE_WIDTH (t) - 2)) - 1) * 2 + 1)))
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+
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+/* The maximum and minimum values for the type of the expression E,
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+   after integer promotion.  E is not evaluated.  */
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+#define _GL_INT_MINIMUM(e)                                              \
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+  (EXPR_SIGNED (e)                                                      \
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+   ? ~ _GL_SIGNED_INT_MAXIMUM (e)                                       \
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+   : _GL_INT_CONVERT (e, 0))
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+#define _GL_INT_MAXIMUM(e)                                              \
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+  (EXPR_SIGNED (e)                                                      \
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+   ? _GL_SIGNED_INT_MAXIMUM (e)                                         \
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+   : _GL_INT_NEGATE_CONVERT (e, 1))
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+#define _GL_SIGNED_INT_MAXIMUM(e)                                       \
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+  (((_GL_INT_CONVERT (e, 1) << (TYPE_WIDTH ((e) + 0) - 2)) - 1) * 2 + 1)
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+
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+/* Work around OpenVMS incompatibility with C99.  */
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+#if !defined LLONG_MAX && defined __INT64_MAX
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+# define LLONG_MAX __INT64_MAX
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+# define LLONG_MIN __INT64_MIN
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+#endif
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+
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+/* This include file assumes that signed types are two's complement without
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+   padding bits; the above macros have undefined behavior otherwise.
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+   If this is a problem for you, please let us know how to fix it for your host.
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+   This assumption is tested by the intprops-tests module.  */
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+
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+/* Does the __typeof__ keyword work?  This could be done by
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+   'configure', but for now it's easier to do it by hand.  */
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+#if (2 <= __GNUC__ \
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+     || (1210 <= __IBMC__ && defined __IBM__TYPEOF__) \
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+     || (0x5110 <= __SUNPRO_C && !__STDC__))
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+# define _GL_HAVE___TYPEOF__ 1
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+#else
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+# define _GL_HAVE___TYPEOF__ 0
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+#endif
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+
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+/* Return 1 if the integer type or expression T might be signed.  Return 0
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+   if it is definitely unsigned.  This macro does not evaluate its argument,
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+   and expands to an integer constant expression.  */
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+#if _GL_HAVE___TYPEOF__
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+# define _GL_SIGNED_TYPE_OR_EXPR(t) TYPE_SIGNED (__typeof__ (t))
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+#else
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+# define _GL_SIGNED_TYPE_OR_EXPR(t) 1
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+#endif
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+
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+/* Bound on length of the string representing an unsigned integer
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+   value representable in B bits.  log10 (2.0) < 146/485.  The
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+   smallest value of B where this bound is not tight is 2621.  */
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+#define INT_BITS_STRLEN_BOUND(b) (((b) * 146 + 484) / 485)
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+
9bb5d6
+/* Bound on length of the string representing an integer type or expression T.
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+   Subtract 1 for the sign bit if T is signed, and then add 1 more for
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+   a minus sign if needed.
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+
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+   Because _GL_SIGNED_TYPE_OR_EXPR sometimes returns 0 when its argument is
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+   signed, this macro may overestimate the true bound by one byte when
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+   applied to unsigned types of size 2, 4, 16, ... bytes.  */
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+#define INT_STRLEN_BOUND(t)                                     \
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+  (INT_BITS_STRLEN_BOUND (TYPE_WIDTH (t) - _GL_SIGNED_TYPE_OR_EXPR (t)) \
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+   + _GL_SIGNED_TYPE_OR_EXPR (t))
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+
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+/* Bound on buffer size needed to represent an integer type or expression T,
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+   including the terminating null.  */
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+#define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)
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+
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+
9bb5d6
+/* Range overflow checks.
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+
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+   The INT_<op>_RANGE_OVERFLOW macros return 1 if the corresponding C
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+   operators might not yield numerically correct answers due to
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+   arithmetic overflow.  They do not rely on undefined or
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+   implementation-defined behavior.  Their implementations are simple
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+   and straightforward, but they are a bit harder to use than the
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+   INT_<op>_OVERFLOW macros described below.
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+
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+   Example usage:
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+
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+     long int i = ...;
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+     long int j = ...;
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+     if (INT_MULTIPLY_RANGE_OVERFLOW (i, j, LONG_MIN, LONG_MAX))
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+       printf ("multiply would overflow");
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+     else
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+       printf ("product is %ld", i * j);
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+
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+   Restrictions on *_RANGE_OVERFLOW macros:
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+
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+   These macros do not check for all possible numerical problems or
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+   undefined or unspecified behavior: they do not check for division
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+   by zero, for bad shift counts, or for shifting negative numbers.
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+
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+   These macros may evaluate their arguments zero or multiple times,
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+   so the arguments should not have side effects.  The arithmetic
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+   arguments (including the MIN and MAX arguments) must be of the same
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+   integer type after the usual arithmetic conversions, and the type
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+   must have minimum value MIN and maximum MAX.  Unsigned types should
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+   use a zero MIN of the proper type.
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+
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+   These macros are tuned for constant MIN and MAX.  For commutative
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+   operations such as A + B, they are also tuned for constant B.  */
9bb5d6
+
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+/* Return 1 if A + B would overflow in [MIN,MAX] arithmetic.
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+   See above for restrictions.  */
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+#define INT_ADD_RANGE_OVERFLOW(a, b, min, max)          \
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+  ((b) < 0                                              \
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+   ? (a) < (min) - (b)                                  \
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+   : (max) - (b) < (a))
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+
9bb5d6
+/* Return 1 if A - B would overflow in [MIN,MAX] arithmetic.
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+   See above for restrictions.  */
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+#define INT_SUBTRACT_RANGE_OVERFLOW(a, b, min, max)     \
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+  ((b) < 0                                              \
9bb5d6
+   ? (max) + (b) < (a)                                  \
9bb5d6
+   : (a) < (min) + (b))
9bb5d6
+
9bb5d6
+/* Return 1 if - A would overflow in [MIN,MAX] arithmetic.
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+   See above for restrictions.  */
9bb5d6
+#define INT_NEGATE_RANGE_OVERFLOW(a, min, max)          \
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+  ((min) < 0                                            \
9bb5d6
+   ? (a) < - (max)                                      \
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+   : 0 < (a))
9bb5d6
+
9bb5d6
+/* Return 1 if A * B would overflow in [MIN,MAX] arithmetic.
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+   See above for restrictions.  Avoid && and || as they tickle
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+   bugs in Sun C 5.11 2010/08/13 and other compilers; see
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+   <https://lists.gnu.org/r/bug-gnulib/2011-05/msg00401.html>.  */
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+#define INT_MULTIPLY_RANGE_OVERFLOW(a, b, min, max)     \
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+  ((b) < 0                                              \
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+   ? ((a) < 0                                           \
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+      ? (a) < (max) / (b)                               \
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+      : (b) == -1                                       \
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+      ? 0                                               \
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+      : (min) / (b) < (a))                              \
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+   : (b) == 0                                           \
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+   ? 0                                                  \
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+   : ((a) < 0                                           \
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+      ? (a) < (min) / (b)                               \
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+      : (max) / (b) < (a)))
9bb5d6
+
9bb5d6
+/* Return 1 if A / B would overflow in [MIN,MAX] arithmetic.
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+   See above for restrictions.  Do not check for division by zero.  */
9bb5d6
+#define INT_DIVIDE_RANGE_OVERFLOW(a, b, min, max)       \
9bb5d6
+  ((min) < 0 && (b) == -1 && (a) < - (max))
9bb5d6
+
9bb5d6
+/* Return 1 if A % B would overflow in [MIN,MAX] arithmetic.
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+   See above for restrictions.  Do not check for division by zero.
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+   Mathematically, % should never overflow, but on x86-like hosts
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+   INT_MIN % -1 traps, and the C standard permits this, so treat this
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+   as an overflow too.  */
9bb5d6
+#define INT_REMAINDER_RANGE_OVERFLOW(a, b, min, max)    \
9bb5d6
+  INT_DIVIDE_RANGE_OVERFLOW (a, b, min, max)
9bb5d6
+
9bb5d6
+/* Return 1 if A << B would overflow in [MIN,MAX] arithmetic.
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+   See above for restrictions.  Here, MIN and MAX are for A only, and B need
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+   not be of the same type as the other arguments.  The C standard says that
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+   behavior is undefined for shifts unless 0 <= B < wordwidth, and that when
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+   A is negative then A << B has undefined behavior and A >> B has
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+   implementation-defined behavior, but do not check these other
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+   restrictions.  */
9bb5d6
+#define INT_LEFT_SHIFT_RANGE_OVERFLOW(a, b, min, max)   \
9bb5d6
+  ((a) < 0                                              \
9bb5d6
+   ? (a) < (min) >> (b)                                 \
9bb5d6
+   : (max) >> (b) < (a))
9bb5d6
+
9bb5d6
+/* True if __builtin_add_overflow (A, B, P) works when P is non-null.  */
9bb5d6
+#if 5 <= __GNUC__ && !defined __ICC
9bb5d6
+# define _GL_HAS_BUILTIN_OVERFLOW 1
9bb5d6
+#else
9bb5d6
+# define _GL_HAS_BUILTIN_OVERFLOW 0
9bb5d6
+#endif
9bb5d6
+
9bb5d6
+/* True if __builtin_add_overflow_p (A, B, C) works.  */
9bb5d6
+#define _GL_HAS_BUILTIN_OVERFLOW_P (7 <= __GNUC__)
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+
9bb5d6
+/* The _GL*_OVERFLOW macros have the same restrictions as the
9bb5d6
+   *_RANGE_OVERFLOW macros, except that they do not assume that operands
9bb5d6
+   (e.g., A and B) have the same type as MIN and MAX.  Instead, they assume
9bb5d6
+   that the result (e.g., A + B) has that type.  */
9bb5d6
+#if _GL_HAS_BUILTIN_OVERFLOW_P
9bb5d6
+# define _GL_ADD_OVERFLOW(a, b, min, max)                               \
9bb5d6
+   __builtin_add_overflow_p (a, b, (__typeof__ ((a) + (b))) 0)
9bb5d6
+# define _GL_SUBTRACT_OVERFLOW(a, b, min, max)                          \
9bb5d6
+   __builtin_sub_overflow_p (a, b, (__typeof__ ((a) - (b))) 0)
9bb5d6
+# define _GL_MULTIPLY_OVERFLOW(a, b, min, max)                          \
9bb5d6
+   __builtin_mul_overflow_p (a, b, (__typeof__ ((a) * (b))) 0)
9bb5d6
+#else
9bb5d6
+# define _GL_ADD_OVERFLOW(a, b, min, max)                                \
9bb5d6
+   ((min) < 0 ? INT_ADD_RANGE_OVERFLOW (a, b, min, max)                  \
9bb5d6
+    : (a) < 0 ? (b) <= (a) + (b)                                         \
9bb5d6
+    : (b) < 0 ? (a) <= (a) + (b)                                         \
9bb5d6
+    : (a) + (b) < (b))
9bb5d6
+# define _GL_SUBTRACT_OVERFLOW(a, b, min, max)                           \
9bb5d6
+   ((min) < 0 ? INT_SUBTRACT_RANGE_OVERFLOW (a, b, min, max)             \
9bb5d6
+    : (a) < 0 ? 1                                                        \
9bb5d6
+    : (b) < 0 ? (a) - (b) <= (a)                                         \
9bb5d6
+    : (a) < (b))
9bb5d6
+# define _GL_MULTIPLY_OVERFLOW(a, b, min, max)                           \
9bb5d6
+   (((min) == 0 && (((a) < 0 && 0 < (b)) || ((b) < 0 && 0 < (a))))       \
9bb5d6
+    || INT_MULTIPLY_RANGE_OVERFLOW (a, b, min, max))
9bb5d6
+#endif
9bb5d6
+#define _GL_DIVIDE_OVERFLOW(a, b, min, max)                             \
9bb5d6
+  ((min) < 0 ? (b) == _GL_INT_NEGATE_CONVERT (min, 1) && (a) < - (max)  \
9bb5d6
+   : (a) < 0 ? (b) <= (a) + (b) - 1                                     \
9bb5d6
+   : (b) < 0 && (a) + (b) <= (a))
9bb5d6
+#define _GL_REMAINDER_OVERFLOW(a, b, min, max)                          \
9bb5d6
+  ((min) < 0 ? (b) == _GL_INT_NEGATE_CONVERT (min, 1) && (a) < - (max)  \
9bb5d6
+   : (a) < 0 ? (a) % (b) != ((max) - (b) + 1) % (b)                     \
9bb5d6
+   : (b) < 0 && ! _GL_UNSIGNED_NEG_MULTIPLE (a, b, max))
9bb5d6
+
9bb5d6
+/* Return a nonzero value if A is a mathematical multiple of B, where
9bb5d6
+   A is unsigned, B is negative, and MAX is the maximum value of A's
9bb5d6
+   type.  A's type must be the same as (A % B)'s type.  Normally (A %
9bb5d6
+   -B == 0) suffices, but things get tricky if -B would overflow.  */
9bb5d6
+#define _GL_UNSIGNED_NEG_MULTIPLE(a, b, max)                            \
9bb5d6
+  (((b) < -_GL_SIGNED_INT_MAXIMUM (b)                                   \
9bb5d6
+    ? (_GL_SIGNED_INT_MAXIMUM (b) == (max)                              \
9bb5d6
+       ? (a)                                                            \
9bb5d6
+       : (a) % (_GL_INT_CONVERT (a, _GL_SIGNED_INT_MAXIMUM (b)) + 1))   \
9bb5d6
+    : (a) % - (b))                                                      \
9bb5d6
+   == 0)
9bb5d6
+
9bb5d6
+/* Check for integer overflow, and report low order bits of answer.
9bb5d6
+
9bb5d6
+   The INT_<op>_OVERFLOW macros return 1 if the corresponding C operators
9bb5d6
+   might not yield numerically correct answers due to arithmetic overflow.
9bb5d6
+   The INT_<op>_WRAPV macros also store the low-order bits of the answer.
9bb5d6
+   These macros work correctly on all known practical hosts, and do not rely
9bb5d6
+   on undefined behavior due to signed arithmetic overflow.
9bb5d6
+
9bb5d6
+   Example usage, assuming A and B are long int:
9bb5d6
+
9bb5d6
+     if (INT_MULTIPLY_OVERFLOW (a, b))
9bb5d6
+       printf ("result would overflow\n");
9bb5d6
+     else
9bb5d6
+       printf ("result is %ld (no overflow)\n", a * b);
9bb5d6
+
9bb5d6
+   Example usage with WRAPV flavor:
9bb5d6
+
9bb5d6
+     long int result;
9bb5d6
+     bool overflow = INT_MULTIPLY_WRAPV (a, b, &result);
9bb5d6
+     printf ("result is %ld (%s)\n", result,
9bb5d6
+             overflow ? "after overflow" : "no overflow");
9bb5d6
+
9bb5d6
+   Restrictions on these macros:
9bb5d6
+
9bb5d6
+   These macros do not check for all possible numerical problems or
9bb5d6
+   undefined or unspecified behavior: they do not check for division
9bb5d6
+   by zero, for bad shift counts, or for shifting negative numbers.
9bb5d6
+
9bb5d6
+   These macros may evaluate their arguments zero or multiple times, so the
9bb5d6
+   arguments should not have side effects.
9bb5d6
+
9bb5d6
+   The WRAPV macros are not constant expressions.  They support only
9bb5d6
+   +, binary -, and *.  The result type must be signed.
9bb5d6
+
9bb5d6
+   These macros are tuned for their last argument being a constant.
9bb5d6
+
9bb5d6
+   Return 1 if the integer expressions A * B, A - B, -A, A * B, A / B,
9bb5d6
+   A % B, and A << B would overflow, respectively.  */
9bb5d6
+
9bb5d6
+#define INT_ADD_OVERFLOW(a, b) \
9bb5d6
+  _GL_BINARY_OP_OVERFLOW (a, b, _GL_ADD_OVERFLOW)
9bb5d6
+#define INT_SUBTRACT_OVERFLOW(a, b) \
9bb5d6
+  _GL_BINARY_OP_OVERFLOW (a, b, _GL_SUBTRACT_OVERFLOW)
9bb5d6
+#if _GL_HAS_BUILTIN_OVERFLOW_P
9bb5d6
+# define INT_NEGATE_OVERFLOW(a) INT_SUBTRACT_OVERFLOW (0, a)
9bb5d6
+#else
9bb5d6
+# define INT_NEGATE_OVERFLOW(a) \
9bb5d6
+   INT_NEGATE_RANGE_OVERFLOW (a, _GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a))
9bb5d6
+#endif
9bb5d6
+#define INT_MULTIPLY_OVERFLOW(a, b) \
9bb5d6
+  _GL_BINARY_OP_OVERFLOW (a, b, _GL_MULTIPLY_OVERFLOW)
9bb5d6
+#define INT_DIVIDE_OVERFLOW(a, b) \
9bb5d6
+  _GL_BINARY_OP_OVERFLOW (a, b, _GL_DIVIDE_OVERFLOW)
9bb5d6
+#define INT_REMAINDER_OVERFLOW(a, b) \
9bb5d6
+  _GL_BINARY_OP_OVERFLOW (a, b, _GL_REMAINDER_OVERFLOW)
9bb5d6
+#define INT_LEFT_SHIFT_OVERFLOW(a, b) \
9bb5d6
+  INT_LEFT_SHIFT_RANGE_OVERFLOW (a, b, \
9bb5d6
+                                 _GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a))
9bb5d6
+
9bb5d6
+/* Return 1 if the expression A <op> B would overflow,
9bb5d6
+   where OP_RESULT_OVERFLOW (A, B, MIN, MAX) does the actual test,
9bb5d6
+   assuming MIN and MAX are the minimum and maximum for the result type.
9bb5d6
+   Arguments should be free of side effects.  */
9bb5d6
+#define _GL_BINARY_OP_OVERFLOW(a, b, op_result_overflow)        \
9bb5d6
+  op_result_overflow (a, b,                                     \
9bb5d6
+                      _GL_INT_MINIMUM (_GL_INT_CONVERT (a, b)), \
9bb5d6
+                      _GL_INT_MAXIMUM (_GL_INT_CONVERT (a, b)))
9bb5d6
+
9bb5d6
+/* Store the low-order bits of A + B, A - B, A * B, respectively, into *R.
9bb5d6
+   Return 1 if the result overflows.  See above for restrictions.  */
9bb5d6
+#define INT_ADD_WRAPV(a, b, r) \
9bb5d6
+  _GL_INT_OP_WRAPV (a, b, r, +, __builtin_add_overflow, INT_ADD_OVERFLOW)
9bb5d6
+#define INT_SUBTRACT_WRAPV(a, b, r) \
9bb5d6
+  _GL_INT_OP_WRAPV (a, b, r, -, __builtin_sub_overflow, INT_SUBTRACT_OVERFLOW)
9bb5d6
+#define INT_MULTIPLY_WRAPV(a, b, r) \
9bb5d6
+  _GL_INT_OP_WRAPV (a, b, r, *, __builtin_mul_overflow, INT_MULTIPLY_OVERFLOW)
9bb5d6
+
9bb5d6
+/* Nonzero if this compiler has GCC bug 68193 or Clang bug 25390.  See:
9bb5d6
+   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68193
9bb5d6
+   https://llvm.org/bugs/show_bug.cgi?id=25390
9bb5d6
+   For now, assume all versions of GCC-like compilers generate bogus
9bb5d6
+   warnings for _Generic.  This matters only for older compilers that
9bb5d6
+   lack __builtin_add_overflow.  */
9bb5d6
+#if __GNUC__
9bb5d6
+# define _GL__GENERIC_BOGUS 1
9bb5d6
+#else
9bb5d6
+# define _GL__GENERIC_BOGUS 0
9bb5d6
+#endif
9bb5d6
+
9bb5d6
+/* Store the low-order bits of A <op> B into *R, where OP specifies
9bb5d6
+   the operation.  BUILTIN is the builtin operation, and OVERFLOW the
9bb5d6
+   overflow predicate.  Return 1 if the result overflows.  See above
9bb5d6
+   for restrictions.  */
9bb5d6
+#if _GL_HAS_BUILTIN_OVERFLOW
9bb5d6
+# define _GL_INT_OP_WRAPV(a, b, r, op, builtin, overflow) builtin (a, b, r)
9bb5d6
+#elif 201112 <= __STDC_VERSION__ && !_GL__GENERIC_BOGUS
9bb5d6
+# define _GL_INT_OP_WRAPV(a, b, r, op, builtin, overflow) \
9bb5d6
+   (_Generic \
9bb5d6
+    (*(r), \
9bb5d6
+     signed char: \
9bb5d6
+       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
9bb5d6
+                        signed char, SCHAR_MIN, SCHAR_MAX), \
9bb5d6
+     short int: \
9bb5d6
+       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
9bb5d6
+                        short int, SHRT_MIN, SHRT_MAX), \
9bb5d6
+     int: \
9bb5d6
+       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
9bb5d6
+                        int, INT_MIN, INT_MAX), \
9bb5d6
+     long int: \
9bb5d6
+       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
9bb5d6
+                        long int, LONG_MIN, LONG_MAX), \
9bb5d6
+     long long int: \
9bb5d6
+       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long long int, \
9bb5d6
+                        long long int, LLONG_MIN, LLONG_MAX)))
9bb5d6
+#else
9bb5d6
+# define _GL_INT_OP_WRAPV(a, b, r, op, builtin, overflow) \
9bb5d6
+   (sizeof *(r) == sizeof (signed char) \
9bb5d6
+    ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
9bb5d6
+                       signed char, SCHAR_MIN, SCHAR_MAX) \
9bb5d6
+    : sizeof *(r) == sizeof (short int) \
9bb5d6
+    ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
9bb5d6
+                       short int, SHRT_MIN, SHRT_MAX) \
9bb5d6
+    : sizeof *(r) == sizeof (int) \
9bb5d6
+    ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
9bb5d6
+                       int, INT_MIN, INT_MAX) \
9bb5d6
+    : _GL_INT_OP_WRAPV_LONGISH(a, b, r, op, overflow))
9bb5d6
+# ifdef LLONG_MAX
9bb5d6
+#  define _GL_INT_OP_WRAPV_LONGISH(a, b, r, op, overflow) \
9bb5d6
+    (sizeof *(r) == sizeof (long int) \
9bb5d6
+     ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
9bb5d6
+                        long int, LONG_MIN, LONG_MAX) \
9bb5d6
+     : _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long long int, \
9bb5d6
+                        long long int, LLONG_MIN, LLONG_MAX))
9bb5d6
+# else
9bb5d6
+#  define _GL_INT_OP_WRAPV_LONGISH(a, b, r, op, overflow) \
9bb5d6
+    _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
9bb5d6
+                     long int, LONG_MIN, LONG_MAX)
9bb5d6
+# endif
9bb5d6
+#endif
9bb5d6
+
9bb5d6
+/* Store the low-order bits of A <op> B into *R, where the operation
9bb5d6
+   is given by OP.  Use the unsigned type UT for calculation to avoid
9bb5d6
+   overflow problems.  *R's type is T, with extrema TMIN and TMAX.
9bb5d6
+   T must be a signed integer type.  Return 1 if the result overflows.  */
9bb5d6
+#define _GL_INT_OP_CALC(a, b, r, op, overflow, ut, t, tmin, tmax) \
9bb5d6
+  (sizeof ((a) op (b)) < sizeof (t) \
9bb5d6
+   ? _GL_INT_OP_CALC1 ((t) (a), (t) (b), r, op, overflow, ut, t, tmin, tmax) \
9bb5d6
+   : _GL_INT_OP_CALC1 (a, b, r, op, overflow, ut, t, tmin, tmax))
9bb5d6
+#define _GL_INT_OP_CALC1(a, b, r, op, overflow, ut, t, tmin, tmax) \
9bb5d6
+  ((overflow (a, b) \
9bb5d6
+    || (EXPR_SIGNED ((a) op (b)) && ((a) op (b)) < (tmin)) \
9bb5d6
+    || (tmax) < ((a) op (b))) \
9bb5d6
+   ? (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 1) \
9bb5d6
+   : (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 0))
9bb5d6
+
9bb5d6
+/* Return the low-order bits of A <op> B, where the operation is given
9bb5d6
+   by OP.  Use the unsigned type UT for calculation to avoid undefined
9bb5d6
+   behavior on signed integer overflow, and convert the result to type T.
9bb5d6
+   UT is at least as wide as T and is no narrower than unsigned int,
9bb5d6
+   T is two's complement, and there is no padding or trap representations.
9bb5d6
+   Assume that converting UT to T yields the low-order bits, as is
9bb5d6
+   done in all known two's-complement C compilers.  E.g., see:
9bb5d6
+   https://gcc.gnu.org/onlinedocs/gcc/Integers-implementation.html
9bb5d6
+
9bb5d6
+   According to the C standard, converting UT to T yields an
9bb5d6
+   implementation-defined result or signal for values outside T's
9bb5d6
+   range.  However, code that works around this theoretical problem
9bb5d6
+   runs afoul of a compiler bug in Oracle Studio 12.3 x86.  See:
9bb5d6
+   https://lists.gnu.org/r/bug-gnulib/2017-04/msg00049.html
9bb5d6
+   As the compiler bug is real, don't try to work around the
9bb5d6
+   theoretical problem.  */
9bb5d6
+
9bb5d6
+#define _GL_INT_OP_WRAPV_VIA_UNSIGNED(a, b, op, ut, t) \
9bb5d6
+  ((t) ((ut) (a) op (ut) (b)))
9bb5d6
+
9bb5d6
+#endif /* _GL_INTPROPS_H */