This patch nadgers the driver's subprocess names to include the driver
name. It results in more informative error messages. For instance,
rather than:
>./xg++ -B./ frob.cc -c -fdump-tree-nope
cc1plus: error: unrecognized command line option '-fdump-tree-nope'
we get:
>./xg++ -B./ frob.cc -c -fdump-tree-nope
xg++(cc1plus): error: unrecognized command line option '-fdump-tree-nope'
Thereby cluing the user into this being a compiler error. (When this
error is buried inside a build log, the poor user can be more confused
as to what this cc1plus thing might be).
I achieve this by taking advantage of the subprocess spawning taking
separate arguments for the program to exec, and the argv[0] value passed
to that program. Because subprocesses can use argv[0] to locate
themselves I propagate the directory name, so that remains as before.
When using valgrind, this substitution is not performed, because
valgrind relies on argv[0] being the program pathname.
The -v output is unaffected, as that is emitted before altering argv[0].
argv[0] is also restored after spawning.
This then allows us to elide process_command's check of whether the
input file exists. That's optimizing for failure, but I suspect is
desired merely to avoid an error of the form:
cc1plus: fatal error: frob.cc: No such file or directory
As you can see process_command does some special handling for lto &
@files, which is kind of icky and now goes away. We get:
xg++(cc1plus): fatal error: frob.cc: No such file or directory
Thoughts? Ok? Stupid idea?
nathan
--
Nathan Sidwell
2019-05-14 Nathan Sidwell <nat...@acm.org>
* gcc.c (execute): Splice current executable name into spawned
argv[0] for better subprocess diagnostics.
(process_command): Do not check if input file exists.
* lib/prune.exp (prune_gcc_output): Adjust collect regexps.
Index: gcc/gcc.c
===================================================================
--- gcc/gcc.c (revision 271131)
+++ gcc/gcc.c (working copy)
@@ -3206,6 +3206,48 @@ execute (void)
int err;
const char *string = commands[i].argv[0];
+ if (commands[i].argv == argbuf.address ())
+ {
+ /* Munge argv[0], the one given in the exec'd command's
+ argv, to include information about from whence it was
+ spawned. We preserve the directory component so the
+ command can determine where it is, but not what it was
+ called. Thus its otherwise-unlocated errors specify
+ something like 'g++(cc1plus)' rather than plain
+ 'cc1plus'. Only do this if argv is the argbuf address,
+ so as to not interfere with valgrind insertion. */
+ size_t slen = strlen (string);
+ size_t plen = strlen (progname);
+ size_t tlen = strlen (commands[i].prog);
+
+ /* Remove the filename component from the path. */
+ while (slen && !IS_DIR_SEPARATOR (string[slen-1]))
+ slen--;
+ char *ren = XNEWVEC (char, slen + plen + tlen + 3);
+ size_t off = 0;
+
+ /* Copy directory, including final dir separator. */
+ memcpy (ren + off, string, slen);
+ off += slen;
+ /* Append our progname. */
+ memcpy (ren + off, progname, plen);
+ off += plen;
+
+ ren[off++] = '(';
+
+ /* Append the plain progname (lacking any os-specific
+ suffix). */
+ memcpy (ren + off, commands[i].prog, tlen);
+ off += tlen;
+
+ ren[off++] = ')';
+
+ /* And a NUL. */
+ ren[off++] = 0;
+
+ commands[i].argv[0] = ren;
+ }
+
errmsg = pex_run (pex,
((i + 1 == n_commands ? PEX_LAST : 0)
| (string == commands[i].prog ? PEX_SEARCH : 0)),
@@ -3220,6 +3262,12 @@ execute (void)
string, errmsg);
}
+ if (commands[i].argv[0] != string)
+ {
+ free (const_cast <char *> (commands[i].argv[0]));
+ commands[i].argv[0] = string;
+ }
+
if (i && string != commands[i].prog)
free (CONST_CAST (char *, string));
}
@@ -4561,44 +4609,11 @@ process_command (unsigned int decoded_op
if (decoded_options[j].opt_index == OPT_SPECIAL_input_file)
{
const char *arg = decoded_options[j].arg;
- const char *p = strrchr (arg, '@');
- char *fname;
- long offset;
- int consumed;
#ifdef HAVE_TARGET_OBJECT_SUFFIX
arg = convert_filename (arg, 0, access (arg, F_OK));
#endif
- /* For LTO static archive support we handle input file
- specifications that are composed of a filename and
- an offset like FNAME@OFFSET. */
- if (p
- && p != arg
- && sscanf (p, "@%li%n", &offset, &consumed) >= 1
- && strlen (p) == (unsigned int)consumed)
- {
- fname = (char *)xmalloc (p - arg + 1);
- memcpy (fname, arg, p - arg);
- fname[p - arg] = '\0';
- /* Only accept non-stdin and existing FNAME parts, otherwise
- try with the full name. */
- if (strcmp (fname, "-") == 0 || access (fname, F_OK) < 0)
- {
- free (fname);
- fname = xstrdup (arg);
- }
- }
- else
- fname = xstrdup (arg);
-
- if (strcmp (fname, "-") != 0 && access (fname, F_OK) < 0)
- {
- bool resp = fname[0] == '@' && access (fname + 1, F_OK) < 0;
- error ("%s: %m", fname + resp);
- }
- else
- add_infile (arg, spec_lang);
+ add_infile (arg, spec_lang);
- free (fname);
continue;
}
Index: gcc/testsuite/lib/prune.exp
===================================================================
--- gcc/testsuite/lib/prune.exp (revision 271131)
+++ gcc/testsuite/lib/prune.exp (working copy)
@@ -37,8 +37,8 @@ proc prune_gcc_output { text } {
regsub -all "(^|\n)\[^\n\]*: . skipping \[0-9\]* instantiation contexts \[^\n\]*" $text "" text
regsub -all "(^|\n)\[^\n\]*: in constexpr expansion \[^\n\]*" $text "" text
regsub -all "(^|\n) inlined from \[^\n\]*" $text "" text
- regsub -all "(^|\n)collect2: error: ld returned \[^\n\]*" $text "" text
- regsub -all "(^|\n)collect: re(compiling|linking)\[^\n\]*" $text "" text
+ regsub -all "(^|\n)\[a-z+]*\\(?collect2\\)?: error: ld returned \[^\n\]*" $text "" text
+ regsub -all "(^|\n)\[a-z+]*\\(?collect\\)?: re(compiling|linking)\[^\n\]*" $text "" text
regsub -all "(^|\n)Please submit.*instructions\[^\n\]*" $text "" text
regsub -all "(^|\n)\[0-9\]\[0-9\]* errors\." $text "" text
regsub -all "(^|\n)(In file included|\[ \]+from)\[^\n\]*" $text "" text
