2003-04-11 Geoffrey Keating <geoffk@apple.com>
+ PR c++/9393
+ * doc/invoke.texi (Debugging Options): Document -frandom-seed.
+ * configure.in: Check for gettimeofday.
+ * tree.c (flag_random_seed): Define.
+ (default_flag_random_seed): New.
+ (append_random_chars): Use flag_random_seed rather than trying
+ to acquire randomness here.
+ * tree.h (default_flag_random_seed): Declare.
+ * toplev.c (display_help): Add -frandom-seed and -fstack-limit-*
+ descriptions.
+ (decode_f_option): Handle -frandom-seed.
+ (print_switch_values): Call default_flag_random_seed.
+ * flags.h (flag_random_seed): Declare.
+ * configure: Regenerate.
+ * config.in: Regenerate.
+ * config/alpha/t-crtfm: Use -frandom-seed.
+
* doc/extend.texi (Empty Structures): New.
* c-pch.c: Include flags.h. Add comments to routines.
-/* config.in. Generated automatically from configure.in by autoheader 2.13. */
+/* config.in. Generated automatically from configure.in by autoheader. */
/* Define if using alloca.c. */
#undef C_ALLOCA
/* Define if you have the getrusage function. */
#undef HAVE_GETRUSAGE
+/* Define if you have the gettimeofday function. */
+#undef HAVE_GETTIMEOFDAY
+
/* Define if you have the getuid function. */
#undef HAVE_GETUID
EXTRA_PARTS += crtfastmath.o
crtfastmath.o: $(srcdir)/config/alpha/crtfastmath.c $(GCC_PASSES)
- $(GCC_FOR_TARGET) $(LIBGCC2_CFLAGS) -c -o crtfastmath.o $(srcdir)/config/alpha/crtfastmath.c
+ $(GCC_FOR_TARGET) $(LIBGCC2_CFLAGS) -frandom-seed=gcc-crtfastmath -c \
+ -o crtfastmath.o $(srcdir)/config/alpha/crtfastmath.c
for ac_func in times clock dup2 kill getrlimit setrlimit atoll atoq \
sysconf strsignal putc_unlocked fputc_unlocked fputs_unlocked \
fwrite_unlocked fprintf_unlocked getrusage nl_langinfo lstat \
- scandir alphasort
+ scandir alphasort gettimeofday
do
echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
echo "configure:3721: checking for $ac_func" >&5
AC_CHECK_FUNCS(times clock dup2 kill getrlimit setrlimit atoll atoq \
sysconf strsignal putc_unlocked fputc_unlocked fputs_unlocked \
fwrite_unlocked fprintf_unlocked getrusage nl_langinfo lstat \
- scandir alphasort)
+ scandir alphasort gettimeofday)
AC_CHECK_TYPE(ssize_t, int)
-fdump-tree-original@r{[}-@var{n}@r{]} @gol
-fdump-tree-optimized@r{[}-@var{n}@r{]} @gol
-fdump-tree-inlined@r{[}-@var{n}@r{]} @gol
--feliminate-dwarf2-dups -fmem-report @gol
--fprofile-arcs -fsched-verbose=@var{n} @gol
+-feliminate-dwarf2-dups -feliminate-unused-debug-types @gol
+-fmem-report -fprofile-arcs @gol
+-frandom-seed=@var{string} -fsched-verbose=@var{n} @gol
-ftest-coverage -ftime-report @gol
-g -g@var{level} -gcoff -gdwarf -gdwarf-1 -gdwarf-1+ -gdwarf-2 @gol
-ggdb -gstabs -gstabs+ -gvms -gxcoff -gxcoff+ @gol
-p -pg -print-file-name=@var{library} -print-libgcc-file-name @gol
-print-multi-directory -print-multi-lib @gol
-print-prog-name=@var{program} -print-search-dirs -Q @gol
--feliminate-unused-debug-types @gol
-save-temps -time}
@item Optimization Options
Dump after function inlining, to @file{@var{file}.inlined}.
@end table
+@item -frandom-seed=@var{string}
+@opindex frandom-string
+This option provides a seed that GCC uses when it would otherwise use
+random numbers. At present, this is used to generate certain symbol names
+that have to be different in every compiled file.
+
+The @var{string} should be different for every file you compile.
+
@item -fsched-verbose=@var{n}
@opindex fsched-verbose
On targets that use instruction scheduling, this option controls the
extern int flag_unit_at_a_time;
+/* A string that's used when a random name is required. NULL means
+ to make it really random. */
+
+extern const char *flag_random_seed;
+
/* True if the given mode has a NaN representation and the treatment of
NaN operands is important. Certain optimizations, such as folding
x * 0 into x, are not correct for NaN operands, and are normally
printf (_(" -fmessage-length=<number> Limits diagnostics messages lengths to <number> characters per line. 0 suppresses line-wrapping\n"));
printf (_(" -fdiagnostics-show-location=[once | every-line] Indicates how often source location information should be emitted, as prefix, at the beginning of diagnostics when line-wrapping\n"));
printf (_(" -ftls-model=[global-dynamic | local-dynamic | initial-exec | local-exec] Indicates the default thread-local storage code generation model\n"));
+ printf (_(" -fstack-limit-register=<register> Trap if the stack goes past <register>\n"));
+ printf (_(" -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>\n"));
+ printf (_(" -frandom-seed=<string> Make compile reproducible using <string>\n"));
+
for (i = ARRAY_SIZE (f_options); i--;)
{
}
else if (!strcmp (arg, "no-stack-limit"))
stack_limit_rtx = NULL_RTX;
+ else if ((option_value = skip_leading_substring (arg, "random-seed=")))
+ flag_random_seed = option_value;
+ else if (!strcmp (arg, "no-random-seed"))
+ flag_random_seed = NULL;
else if (!strcmp (arg, "preprocessed"))
/* Recognize this switch but do nothing. This prevents warnings
about an unrecognized switch if cpplib has not been linked in. */
size_t j;
char **p;
+ /* Fill in the -frandom-seed option, if the user didn't pass it, so
+ that it can be printed below. This helps reproducibility. Of
+ course, the string may never be used, but we can't tell that at
+ this point in the compile. */
+ default_flag_random_seed ();
+
/* Print the options as passed. */
pos = print_single_switch (file, pos, max, indent, *indent ? " " : "", term,
\f
#define FILE_FUNCTION_FORMAT "_GLOBAL__%s_%s"
+const char *flag_random_seed;
+
+/* Set up a default flag_random_seed value, if there wasn't one already. */
+
+void
+default_flag_random_seed (void)
+{
+ unsigned HOST_WIDE_INT value;
+ char *new_random_seed;
+
+ if (flag_random_seed != NULL)
+ return;
+
+ /* Get some more or less random data. */
+#ifdef HAVE_GETTIMEOFDAY
+ {
+ struct timeval tv;
+
+ gettimeofday (&tv, NULL);
+ value = (((unsigned HOST_WIDE_INT) tv.tv_usec << 16)
+ ^ tv.tv_sec ^ getpid ());
+ }
+#else
+ value = getpid ();
+#endif
+
+ /* This slightly overestimates the space required. */
+ new_random_seed = xmalloc (HOST_BITS_PER_WIDE_INT / 3 + 2);
+ sprintf (new_random_seed, HOST_WIDE_INT_PRINT_UNSIGNED, value);
+ flag_random_seed = new_random_seed;
+}
+
/* Appends 6 random characters to TEMPLATE to (hopefully) avoid name
clashes in cases where we can't reliably choose a unique name.
{
static const char letters[]
= "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
- static unsigned HOST_WIDE_INT value;
unsigned HOST_WIDE_INT v;
+ size_t i;
- if (! value)
- {
- struct stat st;
+ default_flag_random_seed ();
- /* VALUE should be unique for each file and must not change between
- compiles since this can cause bootstrap comparison errors. */
-
- if (stat (main_input_filename, &st) < 0)
- {
- /* This can happen when preprocessed text is shipped between
- machines, e.g. with bug reports. Assume that uniqueness
- isn't actually an issue. */
- value = 1;
- }
- else
- {
- /* In VMS, ino is an array, so we have to use both values. We
- conditionalize that. */
-#ifdef VMS
-#define INO_TO_INT(INO) ((int) (INO)[1] << 16 ^ (int) (INO)[2])
-#else
-#define INO_TO_INT(INO) INO
-#endif
- value = st.st_dev ^ INO_TO_INT (st.st_ino) ^ st.st_mtime;
- }
- }
+ /* This isn't a very good hash, but it does guarantee no collisions
+ when the random string is generated by the code above and the time
+ delta is small. */
+ v = 0;
+ for (i = 0; i < strlen (flag_random_seed); i++)
+ v = (v << 4) ^ (v >> (HOST_BITS_PER_WIDE_INT - 4)) ^ flag_random_seed[i];
template += strlen (template);
- v = value;
-
/* Fill in the random bits. */
template[0] = letters[v % 62];
v /= 62;
extern HOST_WIDE_INT all_cases_count PARAMS ((tree, int *));
extern void check_for_full_enumeration_handling PARAMS ((tree));
extern void declare_nonlocal_label PARAMS ((tree));
+extern void default_flag_random_seed PARAMS ((void));
/* If KIND=='I', return a suitable global initializer (constructor) name.
If KIND=='D', return a suitable global clean-up (destructor) name. */
projects / thirdparty / gcc.git / commitdiff
