Re: gnulib-tool bug

[Bruno Haible]

Eric Blake wrote:
> > This looks like a bug to me: \\ expands to nothing. No way to produce a
> > backslash in the replacement.
> 
> I concur.

Thanks. So I'm disabling --posix. Patch appended.

> "... For each other <backslash> encountered, the following 
> character shall lose its special meaning (if any). The meaning of a 
> <backslash> 
> immediately followed by any character other than ’&’, <backslash>, a digit, 
> or 
> the delimiter character used for this command, is unspecified."
> 
> Thus, 's,^,\/,', is non-portable.

Thanks for explaining. So the third of the mentioned sed expressions is not
POSIX compliant. Fixing it, as attached.

Bruno



2009-02-27  Bruno Haible  <address@hidden>

        * gnulib-tool (sed): Don't alias as "sed --posix".
        Reported by Eric Blake.

*** gnulib-tool.orig    2009-02-28 03:14:43.000000000 +0100
--- gnulib-tool 2009-02-28 03:03:37.000000000 +0100
***************
*** 63,86 ****
    AUTOPOINT="${GETTEXTPATH}autopoint"
  fi
  
! # When using GNU sed, turn off as many GNU extensions as possible,
! # to minimize the risk of accidentally using non-portable features.
! # However, do this only for gnulib-tool itself, not for the code that
! # gnulib-tool generates, since we don't want "sed --posix" to leak
! # into makefiles.
! if (alias) > /dev/null 2>&1 && echo | sed --posix -e d >/dev/null 2>&1; then
!   # Define sed as an alias.
!   # It is not always possible to use aliases. Aliases are guaranteed to work
!   # if the executing shell is bash and either it is invoked as /bin/sh or
!   # is a version >= 2.0, supporting shopt. This is the common case.
!   # Two other approaches (use of a variable $sed or of a function func_sed
!   # instead of an alias) require massive, fragile code changes.
!   # An other approach (use of function sed) requires `which sed` - but 'which'
!   # is hard to emulate, due to missing "test -x" on some platforms.
!   if test -n "$BASH_VERSION"; then
!     shopt -s expand_aliases >/dev/null 2>&1
    fi
-   alias sed='sed --posix'
  fi
  
  # sed_noop is a sed expression that does nothing.
--- 63,90 ----
    AUTOPOINT="${GETTEXTPATH}autopoint"
  fi
  
! # Disabled because "sed --posix" is buggy in GNU sed 4.1.5, see
! # <http://lists.gnu.org/archive/html/bug-gnulib/2009-02/msg00225.html>.
! if false; then
!   # When using GNU sed, turn off as many GNU extensions as possible,
!   # to minimize the risk of accidentally using non-portable features.
!   # However, do this only for gnulib-tool itself, not for the code that
!   # gnulib-tool generates, since we don't want "sed --posix" to leak
!   # into makefiles.
!   if (alias) > /dev/null 2>&1 && echo | sed --posix -e d >/dev/null 2>&1; then
!     # Define sed as an alias.
!     # It is not always possible to use aliases. Aliases are guaranteed to work
!     # if the executing shell is bash and either it is invoked as /bin/sh or
!     # is a version >= 2.0, supporting shopt. This is the common case.
!     # Two other approaches (use of a variable $sed or of a function func_sed
!     # instead of an alias) require massive, fragile code changes.
!     # An other approach (use of function sed) requires `which sed` - but
!     # 'which' is hard to emulate, due to missing "test -x" on some platforms.
!     if test -n "$BASH_VERSION"; then
!       shopt -s expand_aliases >/dev/null 2>&1
!     fi
!     alias sed='sed --posix'
    fi
  fi
  
  # sed_noop is a sed expression that does nothing.


2009-02-27  Bruno Haible  <address@hidden>

        * gnulib-tool (func_import): Make the sed expression used to create the
        sed script for updating the .gitignore file POSIX compliant.
        Reported by Eric Blake.

--- gnulib-tool.orig    2009-02-28 03:21:49.000000000 +0100
+++ gnulib-tool 2009-02-28 03:21:36.000000000 +0100
@@ -3571,7 +3571,7 @@
                 echo "Updating $destdir/$dir$ignore (backup in 
$destdir/$dir${ignore}~)"
                 mv -f "$destdir/$dir$ignore" "$destdir/$dir$ignore"~
                 { sed -e 's,/,\\/,g' -e 's,^,/^,' -e 's,$,\$/d,' < 
"$tmp"/ignore-removed
-                  if test -n "$anchor"; then sed -e 's,/,\\/,g' -e 
"s,^,/^${doubly_escaped_anchor}," -e 's,$,\$/d,' < "$tmp"/ignore-removed; fi
+                  if test -n "$anchor"; then sed -e 's,/,\\/,g' -e 
"s,^,/^${doubly_escaped_anchor}," -e 's,$,$/d,' < "$tmp"/ignore-removed; fi
                 } > "$tmp"/sed-ignore-removed
                 { cat "$destdir/$dir$ignore"~
                   sed -e "s|^|$anchor|" < "$tmp"/ignore-added