Never mind about functions.texi. I figured out how to do it.
Here is the new diff and changelog.
libiberty/ChangeLog:
2014-10-18 Anthony Brandon <[email protected]>
* filename_cmp.c (filename_eq): No change.
(canonical_filename_eq): New function to check if file names
are the same.
* functions.texi: Updated with documentation for new function.
gcc/ChangeLog:
2014-10-18 Anthony Brandon <[email protected]>
* 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.
gcc/testsuite/ChangeLog:
2014-10-18 Anthony Brandon <[email protected]>
* gcc.misc-tests/output.exp: New test case for identical input
and output files.
include/ChangeLog:
2014-10-18 Anthony Brandon <[email protected]>
* filenames.h: Add prototype for canonical_filename_eq.
On Sat, Oct 18, 2014 at 12:48 PM, Anthony Brandon
<[email protected]> wrote:
> Hi,
> I'm a new contributor and I don't yet have a copyright assignment or
> commit access.
> I took the patch from
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=36312 and made some
> changes.
> This patch makes GCC check if any of the input files is the same as
> the output file specified with -o, and if so give an error message
> rather than overwrite the input file.
> I moved the canonical_filename_eq to libiberty as suggested in the bug
> report, added some comments, and also created a new test case.
> Testing for the same input and output file names didn't really seem to
> fit into an existing test, so I made a new file based on options.exp.
> I'm not sure if there is a better way to do this.
>
> There is still at least one thing that needs to be done, but I
> couldn't get it to work and that is to update
> libiberty/functions.texi. It says to configure with
> --enable-maintainer-mode, and run
> make stamp-functions, but I get a no such target error.
>
> I bootstrapped on x86_64-linux and tested.
>
> include/ChangeLog:
>
> 2014-10-18 Anthony Brandon <[email protected]>
>
> * filenames.h: Add prototype for canonical_filename_eq.
>
> gcc/ChangeLog:
>
> 2014-10-18 Anthony Brandon <[email protected]>
>
> * 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.
>
> gcc/testsuite/ChangeLog:
>
> 2014-10-18 Anthony Brandon <[email protected]>
>
> * gcc.misc-tests/output.exp: New test case for identical input
> and output files.
>
> libiberty/ChangeLog:
>
> 2014-10-18 Anthony Brandon <[email protected]>
>
> * filename_cmp.c (filename_eq): No change.
> (canonical_filename_eq): New function to check if file names
> are the same.
--
Anthony
diff --git a/gcc/diagnostic-core.h b/gcc/diagnostic-core.h
index a8245de..2fba279 100644
--- a/gcc/diagnostic-core.h
+++ b/gcc/diagnostic-core.h
@@ -68,6 +68,8 @@ extern void error_n (location_t, int, const char *, const
char *, ...)
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);
diff --git a/gcc/diagnostic.c b/gcc/diagnostic.c
index 881da0b..1ef95e8 100644
--- a/gcc/diagnostic.c
+++ b/gcc/diagnostic.c
@@ -1154,6 +1154,23 @@ fatal_error (const char *gmsgid, ...)
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
diff --git a/gcc/gcc.c b/gcc/gcc.c
index 71c76f8..c0f997d 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -1702,17 +1702,15 @@ typedef const char *const_char_p; /* For DEF_VEC_P. */
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. */
@@ -1762,8 +1760,6 @@ 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;
@@ -3713,6 +3709,7 @@ driver_handle_option (struct gcc_options *opts,
#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
@@ -4052,6 +4049,14 @@ process_command (unsigned int decoded_options_count,
CL_DRIVER, &handlers, global_dc);
}
+ if (output_file && strcmp (output_file, "-"))
+ {
+ int i;
+ for (i = 0; i < n_infiles; i++)
+ if (canonical_filename_eq (infiles[i].name, output_file))
+ fatal_error ("output file %s is the same as input 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)
diff --git a/gcc/testsuite/gcc.misc-tests/output.exp
b/gcc/testsuite/gcc.misc-tests/output.exp
new file mode 100644
index 0000000..aac7607
--- /dev/null
+++ b/gcc/testsuite/gcc.misc-tests/output.exp
@@ -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 input" $gcc_output]} {
+ fail "$test (no error printed)"
+ return
+ }
+ pass $test
+}
+
+check_gcc_overwrite_input
+
+gcc_parallel_test_enable 1
diff --git a/gcc/toplev.c b/gcc/toplev.c
index 7df9cc7..c42fda6 100644
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -921,10 +921,15 @@ init_asm_output (const char *name)
}
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
+ fatal_error (UNKNOWN_LOCATION,
+ "output file %s is the same as input 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 %s for writing: %m", asm_file_name);
}
if (!flag_syntax_only)
diff --git a/include/filenames.h b/include/filenames.h
index e799a51..470c5e0 100644
--- a/include/filenames.h
+++ b/include/filenames.h
@@ -90,6 +90,8 @@ 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
diff --git a/libiberty/filename_cmp.c b/libiberty/filename_cmp.c
index 9e16d24..31d33bf 100644
--- a/libiberty/filename_cmp.c
+++ b/libiberty/filename_cmp.c
@@ -24,8 +24,13 @@
#include <string.h>
#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+
#include "filenames.h"
#include "safe-ctype.h"
+#include "libiberty.h"
/*
@@ -190,3 +195,26 @@ 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 first normalizes the file names 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;
+}
diff --git a/libiberty/functions.texi b/libiberty/functions.texi
index 387aee0..48a5546 100644
--- a/libiberty/functions.texi
+++ b/libiberty/functions.texi
@@ -125,6 +125,15 @@ Uses @code{malloc} to allocate storage for @var{nelem}
objects of
@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 first normalizes the file names 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)
@@ -286,7 +295,7 @@ 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.
@@ -303,7 +312,7 @@ 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.
@@ -311,7 +320,7 @@ 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
@@ -320,7 +329,7 @@ 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
