[PATCH driver/36312] should refuse to overwrite input file with output file
Manuel López-Ibáñez
lopezibanez@gmail.com
Sat Nov 8 10:23:00 GMT 2014
This patch is a minor variant of the one approved here:
https://gcc.gnu.org/ml/gcc-patches/2014-11/msg00246.html
fixing the problem with linker parameters (which are stored in infiles).
https://gcc.gnu.org/ml/gcc-patches/2014-11/msg00391.html
The only part that has changed, and thus requires approval, is in
gcc/gcc.c, in particular the condition:
+ if ((!infiles[i].language || infiles[i].language[0] != '*')
+ && canonical_filename_eq (infiles[i].name, output_file))
is new.
Boot&tested on x86_64-linux-gnu with
--enable-languages=c,c++,objc,fortran,ada,obj-c++
OK?
gcc/testsuite/ChangeLog:
2014-11-08 Anthony Brandon <anthony.brandon@gmail.com>
Manuel López-Ibáñez <manu@gcc.gnu.org>
PR driver/36312
* gcc.misc-tests/output.exp: New test case for identical input and
output files.
include/ChangeLog:
2014-11-08 Anthony Brandon <anthony.brandon@gmail.com>
Manuel López-Ibáñez <manu@gcc.gnu.org>
PR driver/36312
* filenames.h: Add prototype for canonical_filename_eq.
gcc/ChangeLog:
2014-11-08 Anthony Brandon <anthony.brandon@gmail.com>
Manuel López-Ibáñez <manu@gcc.gnu.org>
PR driver/36312
* diagnostic-core.h: Add prototype for fatal_error.
* diagnostic.c (fatal_error): New function fatal_error.
* gcc.c (store_arg): Remove have_o_argbuf_index.
(process_command): Check if input and output files are the same.
* toplev.c (init_asm_output): Check if input and output files are
the same.
libiberty/ChangeLog:
2014-11-08 Anthony Brandon <anthony.brandon@gmail.com>
Manuel López-Ibáñez <manu@gcc.gnu.org>
PR driver/36312
* filename_cmp.c (canonical_filename_eq): New function to check if
file names are the same.
* functions.texi: Updated with documentation for new function.
-------------- next part --------------
Index: include/filenames.h
===================================================================
--- include/filenames.h (revision 217234)
+++ include/filenames.h (working copy)
@@ -88,10 +88,12 @@ extern int filename_ncmp (const char *s1
extern hashval_t filename_hash (const void *s);
extern int filename_eq (const void *s1, const void *s2);
+extern int canonical_filename_eq (const char *a, const char *b);
+
#ifdef __cplusplus
}
#endif
#endif /* FILENAMES_H */
Index: libiberty/functions.texi
===================================================================
--- libiberty/functions.texi (revision 217234)
+++ libiberty/functions.texi (working copy)
@@ -123,10 +123,20 @@ is deprecated in favor of @code{memset}.
Uses @code{malloc} to allocate storage for @var{nelem} objects of
@var{elsize} bytes each, then zeros the memory.
@end deftypefn
+@c filename_cmp.c:201
+@deftypefn Extension int canonical_filename_eq (const char *@var{a}, const char *@var{b})
+
+Return non-zero if file names @var{a} and @var{b} are equivalent.
+This function compares the canonical versions of the filenames as returned by
+@code{lrealpath()}, so that so that different file names pointing to the same
+underlying file are treated as being identical.
+
+@end deftypefn
+
@c choose-temp.c:45
@deftypefn Extension char* choose_temp_base (void)
Return a prefix for temporary file names or @code{NULL} if unable to
find one. The current directory is chosen if all else fails so the
@@ -284,11 +294,11 @@ Find the first (least significant) bit s
numbered from right to left, starting with bit 1 (corresponding to the
value 1). If @var{valu} is zero, zero is returned.
@end deftypefn
-@c filename_cmp.c:32
+@c filename_cmp.c:37
@deftypefn Extension int filename_cmp (const char *@var{s1}, const char *@var{s2})
Return zero if the two file names @var{s1} and @var{s2} are equivalent.
If not equivalent, the returned value is similar to what @code{strcmp}
would return. In other words, it returns a negative value if @var{s1}
@@ -301,28 +311,28 @@ the case when the two filenames point to
However, it does handle the fact that on DOS-like file systems, forward
and backward slashes are equal.
@end deftypefn
-@c filename_cmp.c:178
+@c filename_cmp.c:183
@deftypefn Extension int filename_eq (const void *@var{s1}, const void *@var{s2})
Return non-zero if file names @var{s1} and @var{s2} are equivalent.
This function is for use with hashtab.c hash tables.
@end deftypefn
-@c filename_cmp.c:147
+@c filename_cmp.c:152
@deftypefn Extension hashval_t filename_hash (const void *@var{s})
Return the hash value for file name @var{s} that will be compared
using filename_cmp.
This function is for use with hashtab.c hash tables.
@end deftypefn
-@c filename_cmp.c:89
+@c filename_cmp.c:94
@deftypefn Extension int filename_ncmp (const char *@var{s1}, const char *@var{s2}, size_t @var{n})
Return zero if the two file names @var{s1} and @var{s2} are equivalent
in range @var{n}.
If not equivalent, the returned value is similar to what @code{strncmp}
Index: libiberty/filename_cmp.c
===================================================================
--- libiberty/filename_cmp.c (revision 217234)
+++ libiberty/filename_cmp.c (working copy)
@@ -22,12 +22,17 @@
#ifdef HAVE_STRING_H
#include <string.h>
#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+
#include "filenames.h"
#include "safe-ctype.h"
+#include "libiberty.h"
/*
@deftypefn Extension int filename_cmp (const char *@var{s1}, const char *@var{s2})
@@ -188,5 +193,29 @@ int
filename_eq (const void *s1, const void *s2)
{
/* The casts are for -Wc++-compat. */
return filename_cmp ((const char *) s1, (const char *) s2) == 0;
}
+
+/*
+
+@deftypefn Extension int canonical_filename_eq (const char *@var{a}, const char *@var{b})
+
+Return non-zero if file names @var{a} and @var{b} are equivalent.
+This function compares the canonical versions of the filenames as returned by
+@code{lrealpath()}, so that so that different file names pointing to the same
+underlying file are treated as being identical.
+
+@end deftypefn
+
+*/
+
+int
+canonical_filename_eq (const char * a, const char * b)
+{
+ char * ca = lrealpath(a);
+ char * cb = lrealpath(b);
+ int res = filename_eq (ca, cb);
+ free (ca);
+ free (cb);
+ return res;
+}
Index: gcc/diagnostic.c
===================================================================
--- gcc/diagnostic.c (revision 217234)
+++ gcc/diagnostic.c (working copy)
@@ -1161,10 +1161,27 @@ fatal_error (const char *gmsgid, ...)
va_end (ap);
gcc_unreachable ();
}
+/* An error which is severe enough that we make no attempt to
+ continue. Do not use this for internal consistency checks; that's
+ internal_error. Use of this function should be rare. */
+void
+fatal_error (location_t loc, const char *gmsgid, ...)
+{
+ diagnostic_info diagnostic;
+ va_list ap;
+
+ va_start (ap, gmsgid);
+ diagnostic_set_info (&diagnostic, gmsgid, &ap, loc, DK_FATAL);
+ report_diagnostic (&diagnostic);
+ va_end (ap);
+
+ gcc_unreachable ();
+}
+
/* An internal consistency check has failed. We make no attempt to
continue. Note that unless there is debugging value to be had from
a more specific message, or some other good reason, you should use
abort () instead of calling this function directly. */
void
Index: gcc/gcc.c
===================================================================
--- gcc/gcc.c (revision 217234)
+++ gcc/gcc.c (working copy)
@@ -1700,21 +1700,19 @@ typedef const char *const_char_p; /* For
/* Vector of pointers to arguments in the current line of specifications. */
static vec<const_char_p> argbuf;
-/* Position in the argbuf vector containing the name of the output file
- (the value associated with the "-o" flag). */
-
-static int have_o_argbuf_index = 0;
-
/* Were the options -c, -S or -E passed. */
static int have_c = 0;
/* Was the option -o passed. */
static int have_o = 0;
+/* Pointer to output file name passed in with -o. */
+static const char *output_file = 0;
+
/* This is the list of suffixes and codes (%g/%u/%U/%j) and the associated
temp file. If the HOST_BIT_BUCKET is used for %j, no entry is made for
it here. */
static struct temp_name {
@@ -1760,12 +1758,10 @@ clear_args (void)
static void
store_arg (const char *arg, int delete_always, int delete_failure)
{
argbuf.safe_push (arg);
- if (strcmp (arg, "-o") == 0)
- have_o_argbuf_index = argbuf.length ();
if (delete_always || delete_failure)
{
const char *p;
/* If the temporary file we should delete is specified as
part of a joined argument extract the filename. */
@@ -3711,10 +3707,11 @@ driver_handle_option (struct gcc_options
case OPT_o:
have_o = 1;
#if defined(HAVE_TARGET_EXECUTABLE_SUFFIX) || defined(HAVE_TARGET_OBJECT_SUFFIX)
arg = convert_filename (arg, ! have_c, 0);
#endif
+ output_file = arg;
/* Save the output name in case -save-temps=obj was used. */
save_temps_prefix = xstrdup (arg);
/* On some systems, ld cannot handle "-o" without a space. So
split the option from its argument. */
save_switch ("-o", 1, &arg, validated, true);
@@ -4050,10 +4047,20 @@ process_command (unsigned int decoded_op
read_cmdline_option (&global_options, &global_options_set,
decoded_options + j, UNKNOWN_LOCATION,
CL_DRIVER, &handlers, global_dc);
}
+ if (output_file && strcmp (output_file, "-"))
+ {
+ int i;
+ for (i = 0; i < n_infiles; i++)
+ if ((!infiles[i].language || infiles[i].language[0] != '*')
+ && canonical_filename_eq (infiles[i].name, output_file))
+ fatal_error ("input file %qs is the same as output file",
+ output_file);
+ }
+
/* If -save-temps=obj and -o name, create the prefix to use for %b.
Otherwise just make -save-temps=obj the same as -save-temps=cwd. */
if (save_temps_flag == SAVE_TEMPS_OBJ && save_temps_prefix != NULL)
{
save_temps_length = strlen (save_temps_prefix);
Index: gcc/diagnostic-core.h
===================================================================
--- gcc/diagnostic-core.h (revision 217234)
+++ gcc/diagnostic-core.h (working copy)
@@ -66,10 +66,12 @@ extern void error (const char *, ...) AT
extern void error_n (location_t, int, const char *, const char *, ...)
ATTRIBUTE_GCC_DIAG(3,5) ATTRIBUTE_GCC_DIAG(4,5);
extern void error_at (location_t, const char *, ...) ATTRIBUTE_GCC_DIAG(2,3);
extern void fatal_error (const char *, ...) ATTRIBUTE_GCC_DIAG(1,2)
ATTRIBUTE_NORETURN;
+extern void fatal_error (location_t, const char *, ...) ATTRIBUTE_GCC_DIAG(2,3)
+ ATTRIBUTE_NORETURN;
/* Pass one of the OPT_W* from options.h as the second parameter. */
extern bool pedwarn (location_t, int, const char *, ...)
ATTRIBUTE_GCC_DIAG(3,4);
extern bool permerror (location_t, const char *, ...) ATTRIBUTE_GCC_DIAG(2,3);
extern void sorry (const char *, ...) ATTRIBUTE_GCC_DIAG(1,2);
Index: gcc/toplev.c
===================================================================
--- gcc/toplev.c (revision 217234)
+++ gcc/toplev.c (working copy)
@@ -940,14 +940,21 @@ init_asm_output (const char *name)
strcat (dumpname, ".s");
asm_file_name = dumpname;
}
if (!strcmp (asm_file_name, "-"))
asm_out_file = stdout;
- else
+ else if (!canonical_filename_eq (asm_file_name, name))
asm_out_file = fopen (asm_file_name, "w");
+ else
+ /* Use fatal_error (UNKOWN_LOCATION) instead of just fatal_error to
+ prevent gcc from printing the first line in the current file. */
+ fatal_error (UNKNOWN_LOCATION,
+ "input file %qs is the same as output file",
+ asm_file_name);
if (asm_out_file == 0)
- fatal_error ("can%'t open %s for writing: %m", asm_file_name);
+ fatal_error (UNKNOWN_LOCATION,
+ "can%'t open %qs for writing: %m", asm_file_name);
}
if (!flag_syntax_only)
{
targetm.asm_out.file_start ();
Index: gcc/testsuite/gcc.misc-tests/output.exp
===================================================================
--- gcc/testsuite/gcc.misc-tests/output.exp (revision 0)
+++ gcc/testsuite/gcc.misc-tests/output.exp (revision 0)
@@ -0,0 +1,66 @@
+# Copyright (C) 2005-2014 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GCC; see the file COPYING3. If not see
+# <http://www.gnu.org/licenses/>.
+
+# Run GCC with the input file also specified as output file. Check that the
+# compiler prints an error message and does not overwrite the input file.
+
+load_lib gcc-defs.exp
+load_lib target-supports.exp
+
+# These tests don't run runtest_file_p consistently if it
+# doesn't return the same values, so disable parallelization
+# of this *.exp file. The first parallel runtest to reach
+# this will run all the tests serially.
+if ![gcc_parallel_test_run_p output] {
+ return
+}
+
+# I'm not sure if this is needed here. It was in options.exp.
+gcc_parallel_test_enable 0
+
+proc check_gcc_overwrite_input {} {
+ set filename test-[pid]
+ set fd [open $filename.c w]
+ puts $fd "int main (void) \{ return 0; \}"
+ close $fd
+ remote_download host $filename.c
+ set test "input overwrite test"
+ set compiler cc1
+ set gcc_output [gcc_target_compile $filename.c $filename.c executable ""]
+
+ # Is this right, or do I need to use something like remote_upload?
+ set fd [open $filename.c r]
+ set file_data [read $fd]
+ close $fd
+ remote_file build delete $filename.c
+
+ # check if the contents of the input file has changed
+ if {!($file_data eq "int main (void) \{ return 0; \}\n")} {
+ fail "$test (input overwritten)"
+ return
+ }
+
+ # check if the error message was printed
+ if {![regexp -- "same as output" $gcc_output]} {
+ fail "$test (no error printed)"
+ return
+ }
+ pass $test
+}
+
+check_gcc_overwrite_input
+
+gcc_parallel_test_enable 1
More information about the Gcc-patches
mailing list