Re: getting back the quote_ignores_source_dir behavior of -I-

[Daniel Villeneuve <daniel_villeneuve at sympatico dot ca>]

Daniel Villeneuve wrote:

> Zack Weinberg wrote:
>
> > Please resubmit the bugfix and the new option as two separate patches
> > (with the above suggested change, and test cases if you can hack 'em in
> > the dejagnu framework - see gcc.dg/cpp/ for existing examples, and note
> > the 'inc' subdirectory of that directory).
>
> I'll look at this later this week.

Sorry for the other patch that I've sent yesterday, it is fragile because
the handling of -I- is spread between gcc.c::process_command and
c-opts.c::quote_split_chain, and the correctness of the whole relies on the
magic of the specs to get things correct.

Here is a better (more complete) patch for the compatibility problem
between -I, -I- and -iquote.

The approach is an extension of the approach in the preceding patch:
process all the behaviors of -I- within gcc.c::process_command, and remove
all traces of -I- elsewhere in the code.  For this, I had to incorporate
the new option -ignore-source-dir in the patch.

As a summary:

1- A new option, -ignore-source-dir, is added to trigger the
  quote_ignores_source_dir behavior of -I- without any other effects.
2- The first pass over options in process_command detects -I-, fails if -I-
  is used more than once, and issues the warning about -I- being obsolete
  (this was all handled in c-opts.c before).
3- The second pass over options in process_command substitutes
  -ignore-source-dir for -I- and substitutes -iquote for -I when appearing
  prior to -I-.

With this patch, -I- is completely processed in a single place
(process_command) as a rewriting into other standard options.  Ordering of
-iquote and -I options before -I- is preserved. It should be easy to remove
the -I- processing later (all in one place).

2006-02-16  Daniel Villeneuve  <daniel_villeneuve@sympatico.ca>

   * c.opt (-ignore-source-dir): New option, triggering the
   quote_ignores_source_dir behavior of (deprecated) -I-.

   * c-opts.c (quote_chain_split): Removed.
   (c_common_handle_option): No longer process -I- within OPT_I case.
   Add case for OPT_ignore_source_dir.

   * c-incpath.h (ignore_source_dir): Renamed from split_quote_chain.
   * c-inc-path.c (ignore_source_dir): Likewise.  Only keep the
   quote_ignores_source_dir behavior.

   * gcc.c (process_command): Fix side-effect problems of -I- on the
   QUOTE list by transforming -I options that occur before -I- into
   -iquote. Transform -I- into -ignore-source-dir.

   * testsuite/gcc.dg/cpp/iquote.c: New test.
   * testsuite/gcc.dg/cpp/iquote.h: Used along with iquote.c.
   * testsuite/gcc.dg/cpp/inc/iquote.h: Used along with iquote.c.

   * doc/invoke.texi: Document -ignore-source-dir.
   * doc/cpp.texi: Likewise.
   * doc/cppopts.texi: Likewise.

--
Daniel Villeneuve

diff -N -u -p -r gcc-4.0.2/NEWS gcc-4.0.2-dv/NEWS
--- gcc-4.0.2/NEWS    2005-09-28 02:18:15.000000000 -0400
+++ gcc-4.0.2-dv/NEWS    2006-02-19 15:17:36.000000000 -0500
@@ -123,8 +123,8 @@ Caveats
       differently and doesn't need those work-arounds.
     * The  graph-coloring  register  allocator,  formerly enabled by the
       option -fnew-ra, has been discontinued.
-     * -I-  has been deprecated. -iquote is meant to replace the need for
-       this option.
+     * -I-  has been deprecated. -iquote and -ignore-source-dir are meant
+       to replace the need for this option.
     * The MIPS -membedded-pic and -mrnames options have been removed.
     * All  MIPS  targets  now  require the GNU assembler. In particular,
       IRIX  configurations  can  no  longer  use the MIPSpro assemblers,
diff -N -u -p -r gcc-4.0.2/gcc/ChangeLog gcc-4.0.2-dv/gcc/ChangeLog
--- gcc-4.0.2/gcc/ChangeLog    2005-09-20 23:56:04.000000000 -0400
+++ gcc-4.0.2-dv/gcc/ChangeLog    2006-02-19 16:00:32.000000000 -0500
@@ -1,3 +1,28 @@
+2006-02-16  Daniel Villeneuve  <daniel_villeneuve@sympatico.ca>
+
+    * c.opt (-ignore-source-dir): New option, triggering the
+    quote_ignores_source_dir behavior of (deprecated) -I-.
+
+    * c-opts.c (quote_chain_split): Removed.
+    (c_common_handle_option): No longer process -I- within OPT_I case.
+    Add case for OPT_ignore_source_dir.
+
+    * c-incpath.h (ignore_source_dir): Renamed from split_quote_chain.
+    * c-inc-path.c (ignore_source_dir): Likewise.  Only keep the
+    quote_ignores_source_dir behavior.
+
+    * gcc.c (process_command): Fix side-effect problems of -I- on the
+    QUOTE list by transforming -I options that occur before -I- into
+    -iquote. Transform -I- into -ignore-source-dir.
+
+    * testsuite/gcc.dg/cpp/iquote.c: New test.
+    * testsuite/gcc.dg/cpp/iquote.h: Used along with iquote.c.
+    * testsuite/gcc.dg/cpp/inc/iquote.h: Used along with iquote.c.
+
+    * doc/invoke.texi: Document -ignore-source-dir.
+    * doc/cpp.texi: Likewise.
+    * doc/cppopts.texi: Likewise.
+
2005-09-20  Release Manager

    * GCC 4.0.2 released.
diff -N -u -p -r gcc-4.0.2/gcc/c-incpath.c gcc-4.0.2-dv/gcc/c-incpath.c
--- gcc-4.0.2/gcc/c-incpath.c    2005-01-23 10:05:27.000000000 -0500
+++ gcc-4.0.2-dv/gcc/c-incpath.c    2006-02-19 12:09:04.000000000 -0500
@@ -296,18 +296,9 @@ merge_include_chains (cpp_reader *pfile,
    }
}

-/* Use given -I paths for #include "..." but not #include <...>, and
-   don't search the directory of the present file for #include "...".
-   (Note that -I. -I- is not the same as the default setup; -I. uses
-   the compiler's working dir.)  */
void
-split_quote_chain (void)
+ignore_source_dir (void)
{
-  heads[QUOTE] = heads[BRACKET];
-  tails[QUOTE] = tails[BRACKET];
-  heads[BRACKET] = NULL;
-  tails[BRACKET] = NULL;
-  /* This is NOT redundant.  */
  quote_ignores_source_dir = true;
}

diff -N -u -p -r gcc-4.0.2/gcc/c-incpath.h gcc-4.0.2-dv/gcc/c-incpath.h
--- gcc-4.0.2/gcc/c-incpath.h    2005-01-23 10:05:28.000000000 -0500
+++ gcc-4.0.2-dv/gcc/c-incpath.h    2006-02-19 12:08:49.000000000 -0500
@@ -15,7 +15,7 @@ You should have received a copy of the G
along with this program; if not, write to the Free Software
Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

-extern void split_quote_chain (void);
+extern void ignore_source_dir (void);
extern void add_path (char *, int, int, bool);
extern void register_include_chains (cpp_reader *, const char *,
                     const char *, int, int, int);
diff -N -u -p -r gcc-4.0.2/gcc/c-opts.c gcc-4.0.2-dv/gcc/c-opts.c
--- gcc-4.0.2/gcc/c-opts.c    2005-04-30 21:11:56.000000000 -0400
+++ gcc-4.0.2-dv/gcc/c-opts.c    2006-02-19 12:08:36.000000000 -0500
@@ -85,9 +85,6 @@ static bool std_inc = true;
/* Zero disables the C++-specific standard directories for headers.  */
static bool std_cxx_inc = true;

-/* If the quote chain has been split by -I-.  */
-static bool quote_chain_split;
-
/* If -Wunused-macros.  */
static bool warn_unused_macros;

@@ -295,16 +292,7 @@ c_common_handle_option (size_t scode, co
      break;

    case OPT_I:
-      if (strcmp (arg, "-"))
-    add_path (xstrdup (arg), BRACKET, 0, true);
-      else
-    {
-      if (quote_chain_split)
-        error ("-I- specified twice");
-      quote_chain_split = true;
-      split_quote_chain ();
-      inform ("obsolete option -I- used, please use -iquote instead");
-    }
+      add_path (xstrdup (arg), BRACKET, 0, true);
      break;

    case OPT_M:
@@ -790,6 +778,10 @@ c_common_handle_option (size_t scode, co
      add_path (xstrdup (arg), AFTER, 0, true);
      break;

+    case OPT_ignore_source_dir:
+      ignore_source_dir ();
+      break;
+
    case OPT_imacros:
    case OPT_include:
      defer_opt (code, arg);
diff -N -u -p -r gcc-4.0.2/gcc/c.opt gcc-4.0.2-dv/gcc/c.opt
--- gcc-4.0.2/gcc/c.opt    2005-04-30 21:11:57.000000000 -0400
+++ gcc-4.0.2-dv/gcc/c.opt    2006-02-19 12:17:42.000000000 -0500
@@ -739,6 +739,10 @@ idirafter
C ObjC C++ ObjC++ Joined Separate
-idirafter <dir>    Add <dir> to the end of the system include path

+ignore-source-dir
+C ObjC C++ ObjC++
+Ignore source file's directory when searching for #include \"...\" files
+
imacros
C ObjC C++ ObjC++ Joined Separate
-imacros <file>    Accept definition of macros in <file>
diff -N -u -p -r gcc-4.0.2/gcc/doc/cpp.texi gcc-4.0.2-dv/gcc/doc/cpp.texi
--- gcc-4.0.2/gcc/doc/cpp.texi    2005-04-14 13:17:29.000000000 -0400
+++ gcc-4.0.2-dv/gcc/doc/cpp.texi    2006-02-19 15:27:56.000000000 -0500
@@ -898,8 +898,8 @@ This has two effects.  First, directorie
quote marks.  Directories after @option{-I-} are searched for all
headers.  Second, the directory containing the current file is not
searched for anything, unless it happens to be one of the directories
-named by an @option{-I} switch.  @option{-I-} is deprecated, 
@option{-iquote}
-should be used instead.
+named by an @option{-I} switch.  @option{-I-} is deprecated,
+@option{-iquote} and @option{-ignore-source-dir} should be used instead.

@option{-I. -I-} is not the same as no @option{-I} options at all, and does
not cause the same behavior for @samp{<>} includes that @samp{""}
@@ -4045,8 +4045,8 @@ they generally represent bugs in the sna

@item -I- deprecated

-This option has been deprecated in 4.0.  @option{-iquote} is meant to
-replace the need for this option.
+This option has been deprecated in 4.0.  @option{-iquote} and
+@option{-ignore-source-dir} are meant to replace the need for this option.

@item Order of evaluation of @samp{#} and @samp{##} operators

@@ -4140,8 +4140,8 @@ without notice.
@ignore
@c man begin SYNOPSIS
cpp [@option{-D}@var{macro}[=@var{defn}]@dots{}] [@option{-U}@var{macro}]
-    [@option{-I}@var{dir}@dots{}] [@option{-iquote}@var{dir}@dots{}]
-    [@option{-W}@var{warn}@dots{}]
+    [@option{-I}@var{dir}@dots{}] [@option{-ignore-source-dir}]
+    [@option{-iquote}@var{dir}@dots{}] [@option{-W}@var{warn}@dots{}]
    [@option{-M}|@option{-MM}] [@option{-MG}] [@option{-MF} @var{filename}]
    [@option{-MP}] [@option{-MQ} @var{target}@dots{}]
    [@option{-MT} @var{target}@dots{}]
diff -N -u -p -r gcc-4.0.2/gcc/doc/cppopts.texi 
gcc-4.0.2-dv/gcc/doc/cppopts.texi
--- gcc-4.0.2/gcc/doc/cppopts.texi    2005-04-17 07:37:51.000000000 -0400
+++ gcc-4.0.2-dv/gcc/doc/cppopts.texi    2006-02-19 15:28:48.000000000 -0500
@@ -463,6 +463,11 @@ Search @var{dir} for header files, but d
directories specified with @option{-I} and the standard system directories
have been exhausted.  @var{dir} is treated as a system include directory.

+@item -ignore-source-dir
+@opindex ignore-source-dir
+Inhibit the use of the current directory (where the current input file
+came from) as the first search directory for @samp{#include "@var{file}"}.
+
@item -iprefix @var{prefix}
@opindex iprefix
Specify @var{prefix} as the prefix for subsequent @option{-iwithprefix}
diff -N -u -p -r gcc-4.0.2/gcc/doc/invoke.texi 
gcc-4.0.2-dv/gcc/doc/invoke.texi
--- gcc-4.0.2/gcc/doc/invoke.texi    2005-09-02 04:12:30.000000000 -0400
+++ gcc-4.0.2-dv/gcc/doc/invoke.texi    2006-02-19 15:23:18.000000000 -0500
@@ -355,7 +355,7 @@ Objective-C and Objective-C++ Dialects}.

@item Directory Options
@xref{Directory Options,,Options for Directory Search}.
-@gccoptlist{-B@var{prefix}  -I@var{dir}  -iquote@var{dir}  -L@var{dir}  
-specs=@var{file}  -I-}
+@gccoptlist{-B@var{prefix}  -I@var{dir}  -ignore-source-dir  
-iquote@var{dir}  -L@var{dir}  -specs=@var{file}  -I-}

@item Target Options
@c I wrote this xref this way to avoid overfull hbox. -- rms
@@ -6033,6 +6033,11 @@ the ordering for the include_next direct
If you really need to change the search order for system directories,
use the @option{-nostdinc} and/or @option{-isystem} options.

+@item -ignore-source-dir
+@opindex ignore-source-dir
+Inhibit the use of the current directory (where the current input file
+came from) as the first search directory for @samp{#include "@var{file}"}.
+
@item -iquote@var{dir}
@opindex iquote
Add the directory @var{dir} to the head of the list of directories to
@@ -6100,8 +6105,10 @@ are processed in order, from left to rig
@item -I-
@opindex I-
This option has been deprecated.  Please use @option{-iquote} instead for
-@option{-I} directories before the @option{-I-} and remove the 
@option{-I-}.
-Any directories you specify with @option{-I} options before the 
@option{-I-}
+@option{-I} directories before the @option{-I-}, use
+@option{-ignore-source-dir} for not using the source file's directory in
+the include path, and remove the @option{-I-}.  Any directories you
+specify with @option{-I} options before the @option{-I-}
option are searched only for the case of @samp{#include "@var{file}"};
they are not searched for @samp{#include <@var{file}>}.

diff -N -u -p -r gcc-4.0.2/gcc/gcc.c gcc-4.0.2-dv/gcc/gcc.c
--- gcc-4.0.2/gcc/gcc.c    2005-06-06 15:20:29.000000000 -0400
+++ gcc-4.0.2-dv/gcc/gcc.c    2006-02-19 12:29:20.000000000 -0500
@@ -3134,6 +3134,7 @@ process_command (int argc, const char **
  int last_language_n_infiles;
  int have_c = 0;
  int lang_n_infiles = 0;
+  int include_barrier = 0;
#ifdef MODIFY_TARGET_NAME
  int is_modify_target_name;
  int j;
@@ -3755,6 +3756,12 @@ warranty; not even for MERCHANTABILITY o
          if (is_modify_target_name)
        break;
#endif
+              if (! strcmp (argv[i], "-I-")) {
+                if (include_barrier)
+                  fatal ("-I- specified twice");
+                include_barrier = 1;
+                error ("warning: obsolete option -I- used, please use 
-iquote/-ignore-source-dir instead");
+              }

          n_switches++;

@@ -4006,6 +4013,31 @@ warranty; not even for MERCHANTABILITY o
          continue;
        }
      switches[n_switches].part1 = p;
+
+          if (include_barrier)
+            {
+              /* Substitute -I options that precede -I- with -iquote ones.
+                 Substitute -I- with -ignore-source-dir. */
+              if (c == 'I')
+                {
+                  if (p[1] == '-')
+                    {
+                      include_barrier = 0;
+                      switches[n_switches].part1 = "ignore-source-dir";
+                    }
+                  else if (p[1] == 0)
+                    switches[n_switches].part1 = "iquote";
+                  else
+                    {
+                      int len = strlen (p);
+                      char *q = xmalloc (len + sizeof ("iquote") - 1);
+                      memcpy (q, "iquote", sizeof ("iquote") - 1);
+                      memcpy (q + sizeof ("iquote") - 1, p + 1, len);
+                      switches[n_switches].part1 = q;
+                    }
+                }
+            }
+
      /* Deal with option arguments in separate argv elements.  */
      if ((SWITCH_TAKES_ARG (c) > (p[1] != 0))
          || WORD_SWITCH_TAKES_ARG (p))
diff -N -u -p -r gcc-4.0.2/gcc/testsuite/gcc.dg/cpp/inc/iquote.h 
gcc-4.0.2-dv/gcc/testsuite/gcc.dg/cpp/inc/iquote.h
--- gcc-4.0.2/gcc/testsuite/gcc.dg/cpp/inc/iquote.h    1969-12-31 
19:00:00.000000000 -0500
+++ gcc-4.0.2-dv/gcc/testsuite/gcc.dg/cpp/inc/iquote.h    2006-02-17 
15:00:49.000000000 -0500
@@ -0,0 +1 @@
+#define A 1
diff -N -u -p -r gcc-4.0.2/gcc/testsuite/gcc.dg/cpp/iquote.c 
gcc-4.0.2-dv/gcc/testsuite/gcc.dg/cpp/iquote.c
--- gcc-4.0.2/gcc/testsuite/gcc.dg/cpp/iquote.c    1969-12-31 
19:00:00.000000000 -0500
+++ gcc-4.0.2-dv/gcc/testsuite/gcc.dg/cpp/iquote.c    2006-02-17 
16:42:16.000000000 -0500
@@ -0,0 +1,9 @@
+/* { dg-do preprocess } */
+/* { dg-options "-iquote $srcdir/gcc.dg/cpp/inc -I $srcdir/gcc.dg/cpp 
-I-" } */
+
+#include "iquote.h"
+#if A != 1
+# error -iquote was not preserved by later use of -I-
+#endif
+
+/* { dg-error "obsolete option -I- used" "warning message about 
deprecated -I-" { target *-*-* } 0 } */
diff -N -u -p -r gcc-4.0.2/gcc/testsuite/gcc.dg/cpp/iquote.h 
gcc-4.0.2-dv/gcc/testsuite/gcc.dg/cpp/iquote.h
--- gcc-4.0.2/gcc/testsuite/gcc.dg/cpp/iquote.h    1969-12-31 
19:00:00.000000000 -0500
+++ gcc-4.0.2-dv/gcc/testsuite/gcc.dg/cpp/iquote.h    2006-02-17 
15:00:54.000000000 -0500
@@ -0,0 +1 @@
+#define A 2