diff -uNr a/vtools/Makefile b/vtools/Makefile
--- a/vtools/Makefile ae3d7fe005038f18760ef9c78e0aa83bead91fe39020238ff712e46cd52682d0da8ddf2067cdc77247c1466564caf7089b5670cb7ea684b0076f7aa125945351
+++ b/vtools/Makefile 30959920906cdf36872b949334b762f96f0349ece83b040d67c1d551e4deb436aec54afe6767b1ef1e721d99550c72e3d2a5cc83537dc622d50ca93d9261e19d
@@ -30,7 +30,7 @@
 OBJECTS=$(SRCS:.c=.o)
 
 vdiff: $(SOURCES) $(HEADERS)
-	$(CC) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) -std=c99 -Ilib/ -Isrc/ -o $@ $(SOURCES)
+	$(CC) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) -std=c99 -pedantic -Ilib/ -Isrc/ -o $@ $(SOURCES)
 
 clean:
 	@rm -f vdiff
diff -uNr a/vtools/lib/xalloc.h b/vtools/lib/xalloc.h
--- a/vtools/lib/xalloc.h 2146359188e16e7186846ae0b1026dc41bb7ec2c58fce67d3f02f99bdb851f9325483084b55ffd5bcb4b0d36c08799bf3198baaedf7595b6e0ee85a042806446
+++ b/vtools/lib/xalloc.h bb116548d11fb1b72bd214fdcbc29bdc260a10783555acb33972f9fea19332da586048e72aed60cf809dab53dacb8d037e12a9de28709e8f1c67aca1e9b9e3de
@@ -10,7 +10,7 @@
    gnulib's xalloc-die module.  This is the function to call when one
    wants the program to die because of a memory allocation
    failure.  */
-extern _Noreturn void xalloc_die(void);
+extern void xalloc_die(void) __attribute__((noreturn));
 
 void *xmalloc(size_t s);
 void *xzalloc(size_t s);
diff -uNr a/vtools/manifest b/vtools/manifest
--- a/vtools/manifest aab77ccf9c4fa86348f84d661509cf482f958d1a1ed4a55f608683510a8c5ab3e3a12e6c9fa61b6ddf31a493d5be586ef7362d00e1d91542a130b27ec0dc5ad3
+++ b/vtools/manifest 29ca97ffc8fcd1d9a08809f46d6dfbc58da2e139d63001e84b53fe027c7cda61d3170320d097d092b5c0e4e2886a984f17fe94e9988f26c4bcde526be3fe5efc
@@ -1 +1,2 @@
 510300 phf vtools_genesis Initial release of vtools. Genesis contains stripped down version of diffutils 3.6, with most of functionality not relevant to vpatch removed.
+511300 phf vdiff_fixes_newline_gcc Fixes for C99 compatability, support for "No newline at end of file" directive.
diff -uNr a/vtools/src/analyze.c b/vtools/src/analyze.c
--- a/vtools/src/analyze.c 7c13ede685f2c92f24a015e44b9609494e4d5da9bc6a192b62a9cab92f36c2543f5092fdadd7436feac45ca0ab54d19ea0692848c5c94f9819b885beec08e179
+++ b/vtools/src/analyze.c 0626cff1e1871b60ebe1843368954151aa16905f5a26a3bc9a0e9df97eab432042377a5e85928ae3144f88800c8691fa7d6aa362529fa37ea789252c540fd520
@@ -579,14 +579,6 @@
             p = e->link;
             free(e);
         }
-
-        for (f = 0; f < 2; ++f)
-            if (cmp->file[f].missing_newline) {
-                error(0, 0, "%s: %s\n",
-                      file_label[f] ? file_label[f] : cmp->file[f].name,
-                      "No newline at end of file");
-                changes = 2;
-            }
     }
 
     if (cmp->file[0].buffer != cmp->file[1].buffer)
diff -uNr a/vtools/src/io.c b/vtools/src/io.c
--- a/vtools/src/io.c 9ab0950eff37136222dc461537f8448ebc36dff595e77af294e48f9142657ed6da78d72c232ecc890e28ba75a2160d7ab3a09e1a7aa61c50ac95c7a747ef2b7a
+++ b/vtools/src/io.c 7106411c84c6bc2d4ea1027d66b6b1a6278106c5fc2d9c4f990d8d4d762eddeda8eac3441bf3b40129167750b56d210228c2a0e437a707e89fe32de1a4237e99
@@ -196,6 +196,15 @@
         bucket = &buckets[h % nbuckets];
         length = p - ip - 1;
 
+        if (p == bufend
+            && current->missing_newline) {
+            /* The last line is incomplete.  If the line cannot
+               compare equal to any complete line, put it into
+               buckets[-1] so that it can compare equal only to the
+               other file's incomplete line (if one exists).  */
+                bucket = &buckets[-1];
+        }
+
         for (i = *bucket;; i = eqs[i].next)
             if (!i) {
                 /* Create a new equivalence class in this bucket.  */
@@ -271,9 +280,9 @@
         linbuf[line] = p;
 
         if (p == bufend) {
-            /* If the last line is incomplete and we do not silently
-               complete lines, don't count its appended newline.  */
-            if (current->missing_newline && false) /* our output style not robust */
+            /* If the last line is incomplete, don't count its
+               appended newline.  */
+            if (current->missing_newline)
                 linbuf[line]--;
             break;
         }
@@ -395,10 +404,9 @@
 
         /* Don't mistakenly count missing newline as part of
            prefix.  */
-        if (false
-            && ((buffer0 + n0 - filevec[0].missing_newline < p0)
-                !=
-                (buffer1 + n1 - filevec[1].missing_newline < p1)))
+        if ((buffer0 + n0 - filevec[0].missing_newline < p0)
+            !=
+            (buffer1 + n1 - filevec[1].missing_newline < p1))
             p0--, p1--;
     }