Re: [PATCH] depcomp: recognize tabs as whitespace in the dashmstdout mode

[Peter Rosin]

Stefano Lattarini skrev 2012-02-03 09:35:
> Hi Peter.
> 
> On 02/03/2012 08:58 AM, Peter Rosin wrote:
>> Commit Release-1-7-2b-2-gf03ceab "Cope with DOS filenames in
>> dependencies." inadvertently converted tabs into spaces.
>>
>> * lib/depcomp (dashmstdout): Add a tab character to all sets
>> matching whitespace.
>> ---
>>  lib/depcomp |    6 +++---
>>  1 files changed, 3 insertions(+), 3 deletions(-)
>>
>>
>> I know the Tru64 patch to depcomp is out there, and will wait with
>> pushing this one until that one has been processed, but I just wanted
>> to get this out...
>>
> Don't worry about that patch, your objection to how the depcomp.tap
> test is written makes a lot of sense (unfortunately for me), so I now
> think the right fix for bug #10434 will be to change the test case
> instead of the depcomp script.
> 
>> Ok for msvc?
>>
> Almost...  to avoid similar regressions in the future, I think we
> could introduce a new '$tab' variable and use that instead...  and
> then, for extra safety, we might even add a sanity check like:
> 
>   case "$tab" in *\ *) fatal "\$tab is not a TAB";; esac
> 
> early in the script, to ensure $tab is not messed up by editors or
> plain old carelessness.
> 
> WDYT?

I'd rather do that in a follow-up, like below, so that the real change
in the above patch isn't hidden in the churn.  Ok?  No sanity checks
included, but that seems way overkill to me...

Cheers,
Peter




>From 3654caed044041bcfa0f4007c4deb2ed7b582557 Mon Sep 17 00:00:00 2001
From: Peter Rosin <address@hidden>
Date: Fri, 3 Feb 2012 09:56:04 +0100
Subject: [PATCH] depcomp: try to prevent whitespace regressions

Suggested by Stefano Lattarini.

* lib/depcomp: Add $tab and $nl variables and use them
throughout.
---
 lib/depcomp |   40 ++++++++++++++++++++--------------------
 1 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/lib/depcomp b/lib/depcomp
index f2681b9..9a42897 100755
--- a/lib/depcomp
+++ b/lib/depcomp
@@ -1,7 +1,7 @@
 #! /bin/sh
 # depcomp - compile a program generating dependencies as side-effects
 
-scriptversion=2012-02-03.07; # UTC
+scriptversion=2012-02-03.08; # UTC
 
 # Copyright (C) 1999, 2000, 2003, 2004, 2005, 2006, 2007, 2009, 2010,
 # 2011, 2012 Free Software Foundation, Inc.
@@ -57,6 +57,12 @@ EOF
     ;;
 esac
 
+# A tabulation character.
+tab='  '
+# A newline character.
+nl='
+'
+
 if test -z "$depmode" || test -z "$source" || test -z "$object"; then
   echo "depcomp: Variables source, object and depmode must be set" 1>&2
   exit 1
@@ -162,8 +168,7 @@ gcc)
 ## typically no way to rebuild the header).  We avoid this by adding
 ## dummy dependencies for each header file.  Too bad gcc doesn't do
 ## this for us directly.
-  tr ' ' '
-' < "$tmpdepfile" |
+  tr ' ' $nl < "$tmpdepfile" |
 ## Some versions of gcc put a space before the `:'.  On the theory
 ## that the space means something, we add a space to the output as
 ## well.  hp depmode also adds that space, but also prefixes the VPATH
@@ -205,16 +210,13 @@ sgi)
     # IRIX 6.2 sed, 8192 in IRIX 6.5).  We also remove comment lines;
     # the IRIX cc adds comments like `#:fec' to the end of the
     # dependency line.
-    tr ' ' '
-' < "$tmpdepfile" \
+    tr ' ' $nl < "$tmpdepfile" \
     | sed -e 's/^.*\.o://' -e 's/#.*$//' -e '/^$/ d' | \
-    tr '
-' ' ' >> "$depfile"
+    tr $nl ' ' >> "$depfile"
     echo >> "$depfile"
 
     # The second pass generates a dummy entry for each header file.
-    tr ' ' '
-' < "$tmpdepfile" \
+    tr ' ' $nl < "$tmpdepfile" \
    | sed -e 's/^.*\.o://' -e 's/#.*$//' -e '/^$/ d' -e 's/$/:/' \
    >> "$depfile"
   else
@@ -264,7 +266,7 @@ aix)
     # `$object: dependent.h' and one to simply `dependent.h:'.
     sed -e "s,^.*\.[a-z]*:,$object:," < "$tmpdepfile" > "$depfile"
     # That's a tab and a space in the [].
-    sed -e 's,^.*\.[a-z]*:[     ]*,,' -e 's,$,:,' < "$tmpdepfile" >> "$depfile"
+    sed -e 's,^.*\.[a-z]*:['$tab' ]*,,' -e 's,$,:,' < "$tmpdepfile" >> 
"$depfile"
   else
     # The sourcefile does not contain any dependencies, so just
     # store a dummy comment line, to avoid errors with the Makefile
@@ -408,7 +410,7 @@ tru64)
    if test -f "$tmpdepfile"; then
       sed -e "s,^.*\.[a-z]*:,$object:," < "$tmpdepfile" > "$depfile"
       # That's a tab and a space in the [].
-      sed -e 's,^.*\.[a-z]*:[   ]*,,' -e 's,$,:,' < "$tmpdepfile" >> "$depfile"
+      sed -e 's,^.*\.[a-z]*:['$tab' ]*,,' -e 's,$,:,' < "$tmpdepfile" >> 
"$depfile"
    else
       echo "#dummy" > "$depfile"
    fi
@@ -443,11 +445,11 @@ msvc7)
   p
 }' | $cygpath_u | sort -u | sed -n '
 s/ /\\ /g
-s/\(.*\)/      \1 \\/p
+s/\(.*\)/'$tab'\1 \\/p
 s/.\(.*\) \\/\1:/
 H
 $ {
-  s/.*/        /
+  s/.*/'$tab'/
   G
   p
 }' >> "$depfile"
@@ -502,11 +504,10 @@ dashmstdout)
   # in the target name.  This is to cope with DOS-style filenames:
   # a dependency such as `c:/foo/bar' could be seen as target `c' otherwise.
   "$@" $dashmflag |
-    sed 's:^[   ]*[^:   ][^:][^:]*\:[   ]*:'"$object"'\: :' > "$tmpdepfile"
+    sed 's:^['$tab' ]*[^:'$tab' ][^:][^:]*\:['$tab' ]*:'"$object"'\: :' > 
"$tmpdepfile"
   rm -f "$depfile"
   cat < "$tmpdepfile" > "$depfile"
-  tr ' ' '
-' < "$tmpdepfile" | \
+  tr ' ' $nl < "$tmpdepfile" | \
 ## Some versions of the HPUX 10.20 sed can't process this invocation
 ## correctly.  Breaking it into two sed invocations is a workaround.
     sed -e 's/^\\$//' -e '/^$/d' -e '/:$/d' | sed -e 's/$/ :/' >> "$depfile"
@@ -562,8 +563,7 @@ makedepend)
   # makedepend may prepend the VPATH from the source file name to the object.
   # No need to regex-escape $object, excess matching of '.' is harmless.
   sed "s|^.*\($object *:\)|\1|" "$tmpdepfile" > "$depfile"
-  sed '1,2d' "$tmpdepfile" | tr ' ' '
-' | \
+  sed '1,2d' "$tmpdepfile" | tr ' ' $nl | \
 ## Some versions of the HPUX 10.20 sed can't process this invocation
 ## correctly.  Breaking it into two sed invocations is a workaround.
     sed -e 's/^\\$//' -e '/^$/d' -e '/:$/d' | sed -e 's/$/ :/' >> "$depfile"
@@ -652,8 +652,8 @@ msvisualcpp)
   sed -n '/^#line [0-9][0-9]* "\([^"]*\)"/ s::\1:p' | $cygpath_u | sort -u > 
"$tmpdepfile"
   rm -f "$depfile"
   echo "$object : \\" > "$depfile"
-  sed < "$tmpdepfile" -n -e 's% %\\ %g' -e '/^\(.*\)$/ s::     \1 \\:p' >> 
"$depfile"
-  echo "       " >> "$depfile"
+  sed < "$tmpdepfile" -n -e 's% %\\ %g' -e '/^\(.*\)$/ s::'$tab'\1 \\:p' >> 
"$depfile"
+  echo "$tab" >> "$depfile"
   sed < "$tmpdepfile" -n -e 's% %\\ %g' -e '/^\(.*\)$/ s::\1\::p' >> "$depfile"
   rm -f "$tmpdepfile"
   ;;
-- 
1.7.5.1