remove doubled words, e.g., s/to to/to/, and fix related typos

I found that some doubled words had snuck back into projects from which
I'd already removed them, so now there's a "syntax-check" makefile rule in
gnulib to help prevent recurrence.

Running the command below spotted a few in git, too:

  git ls-files | xargs perl -0777 -n \
    -e 'while (/\b(then?|[iao]n|i[fst]|but|f?or|at|and|[dt])\s+\1\b/gims)' \
    -e '{$n=($` =~ tr/\n/\n/ + 1); ($v=$&)=~s/\n/\\n/g;' \
    -e 'print "$ARGV:$n:$v\n"}'

Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches
index c3b0816..c6a5032 100644
--- a/Documentation/SubmittingPatches
+++ b/Documentation/SubmittingPatches
@@ -276,7 +276,7 @@
 
 If you like, you can put extra tags at the end:
 
-1. "Reported-by:" is used to to credit someone who found the bug that
+1. "Reported-by:" is used to credit someone who found the bug that
    the patch attempts to fix.
 2. "Acked-by:" says that the person who is more familiar with the area
    the patch attempts to modify liked the patch.
@@ -608,4 +608,3 @@
 Just make sure to disable line wrapping in the email client (GMail web
 interface will line wrap no matter what, so you need to use a real
 IMAP client).
-
diff --git a/Documentation/git-fetch.txt b/Documentation/git-fetch.txt
index 67d2214..60ac8d2 100644
--- a/Documentation/git-fetch.txt
+++ b/Documentation/git-fetch.txt
@@ -34,7 +34,7 @@
 those missing tags.  If the other end has tags that point at
 branches you are not interested in, you will not get them.
 
-'git fetch' can fetch from either a single named repository, or
+'git fetch' can fetch from either a single named repository,
 or from several repositories at once if <group> is given and
 there is a remotes.<group> entry in the configuration file.
 (See linkgit:git-config[1]).
diff --git a/Documentation/git-pack-objects.txt b/Documentation/git-pack-objects.txt
index 08c89d2..20c8551 100644
--- a/Documentation/git-pack-objects.txt
+++ b/Documentation/git-pack-objects.txt
@@ -115,7 +115,7 @@
 
 --honor-pack-keep::
 	This flag causes an object already in a local pack that
-	has a .keep file to be ignored, even if it it would have
+	has a .keep file to be ignored, even if it would have
 	otherwise been packed.
 
 --incremental::
diff --git a/compat/mingw.c b/compat/mingw.c
index 878b1de..4423961 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1130,7 +1130,7 @@
 
 /*
  * Note, this isn't a complete replacement for getaddrinfo. It assumes
- * that service contains a numerical port, or that it it is null. It
+ * that service contains a numerical port, or that it is null. It
  * does a simple search using gethostbyname, and returns one IPv4 host
  * if one was found.
  */
diff --git a/compat/nedmalloc/malloc.c.h b/compat/nedmalloc/malloc.c.h
index 87260d2..ff7c2c4 100644
--- a/compat/nedmalloc/malloc.c.h
+++ b/compat/nedmalloc/malloc.c.h
@@ -100,7 +100,7 @@
 
        If you don't like either of these options, you can define
        CORRUPTION_ERROR_ACTION and USAGE_ERROR_ACTION to do anything
-       else. And if if you are sure that your program using malloc has
+       else. And if you are sure that your program using malloc has
        no errors or vulnerabilities, you can define INSECURE to 1,
        which might (or might not) provide a small performance improvement.
 
@@ -2279,12 +2279,12 @@
   of the same size are arranged in a circularly-linked list, with only
   the oldest chunk (the next to be used, in our FIFO ordering)
   actually in the tree.  (Tree members are distinguished by a non-null
-  parent pointer.)  If a chunk with the same size an an existing node
+  parent pointer.)  If a chunk with the same size as an existing node
   is inserted, it is linked off the existing node using pointers that
   work in the same way as fd/bk pointers of small chunks.
 
   Each tree contains a power of 2 sized range of chunk sizes (the
-  smallest is 0x100 <= x < 0x180), which is is divided in half at each
+  smallest is 0x100 <= x < 0x180), which is divided in half at each
   tree level, with the chunks in the smaller half of the range (0x100
   <= x < 0x140 for the top nose) in the left subtree and the larger
   half (0x140 <= x < 0x180) in the right subtree.  This is, of course,
@@ -3943,7 +3943,7 @@
     least-preferred order):
     1. A call to MORECORE that can normally contiguously extend memory.
        (disabled if not MORECORE_CONTIGUOUS or not HAVE_MORECORE or
-       or main space is mmapped or a previous contiguous call failed)
+       main space is mmapped or a previous contiguous call failed)
     2. A call to MMAP new space (disabled if not HAVE_MMAP).
        Note that under the default settings, if MORECORE is unable to
        fulfill a request, and HAVE_MMAP is true, then mmap is
@@ -5748,5 +5748,3 @@
 	 structure of old version,  but most details differ.)
 
 */
-
-
diff --git a/gitweb/README b/gitweb/README
index 4a67393..a92bde7 100644
--- a/gitweb/README
+++ b/gitweb/README
@@ -29,7 +29,7 @@
    The filesystem traversing limit for getting the project list; the number
    is taken as depth relative to the projectroot.  It is used when
    GITWEB_LIST is a directory (or is not set; then project root is used).
-   Is is meant to speed up project listing on large work trees by limiting
+   This is meant to speed up project listing on large work trees by limiting
    search depth.  [Default: 2007]
  * GITWEB_LIST
    Points to a directory to scan for projects (defaults to project root
diff --git a/sha1_file.c b/sha1_file.c
index df0edba..889fe71 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1534,7 +1534,7 @@
 	enum object_type type;
 
 	/* use_pack() assures us we have [base, base + 20) available
-	 * as a range that we can look at at.  (Its actually the hash
+	 * as a range that we can look at.  (Its actually the hash
 	 * size that is assured.)  With our object header encoding
 	 * the maximum deflated object size is 2^137, which is just
 	 * insane, so we know won't exceed what we have been given.
diff --git a/vcs-svn/trp.txt b/vcs-svn/trp.txt
index 5ca6b42..177ebca 100644
--- a/vcs-svn/trp.txt
+++ b/vcs-svn/trp.txt
@@ -96,7 +96,7 @@
 
 node_type *foo_nsearch(struct trp_root \*treap, node_type \*key)::
 
-	Like `foo_search`, but if if the key is missing return what
+	Like `foo_search`, but if the key is missing return what
 	would be key's successor, were key in treap (NULL if no
 	successor).