diff --git a/LOG b/LOG
index 1be2605453..9b161f4afb 100644
--- a/LOG
+++ b/LOG
@@ -24,3 +24,15 @@
   so they show up in the Windows workarea c directory.
     cmacros.ss,
     fasl.c, number.c, c/Mf-base, c/Makefile.{t,}{i3,a6}nt
+- The scheme.h definition of Sfixnum(x) now uses multiply rather than
+  left shift to avoid counting on the behavior of << on negative numbers,
+  which is undefined in C.
+    mkheader.ss
+- Fixed a couple of casts, one harmless and the other causing
+  Sinteger64_value to return 0 for the most-negative I64 on 32-bit
+  builds.
+    number.c
+- The configure-generated Makefile distclean target no longer removes
+  zlib and nanopass, since they are logically part of the git clone.
+  It does run make distclean in zlib.
+    makefiles/Makefile.in
diff --git a/c/number.c b/c/number.c
index d27f7dfe0c..a25b4e216d 100644
--- a/c/number.c
+++ b/c/number.c
@@ -289,7 +289,7 @@ I32 S_int32_value(who, x) char *who; ptr x; {
     if (!BIGSIGN(x)) return (I32)u;
     if (u < ((U32)1 << 31)) return -(I32)u;
     if (u > ((U32)1 << 31)) S_error1(who, "~s is out of range", x);
-    return (iptr)0x80000000;
+    return (I32)0x80000000;
   }
 #endif /* (fixnum_bits > 32) */
 
@@ -320,7 +320,7 @@ I64 S_int64_value(who, x) char *who; ptr x; {
     if (!BIGSIGN(x)) return (I64)u;
     if (u < ((U64)1 << 63)) return -(I64)u;
     if (u > ((U64)1 << 63)) S_error1(who, "~s is out of range", x);
-    return (iptr)0x8000000000000000;
+    return (I64)0x8000000000000000;
   }
 
   S_error1(who, "~s is not an integer", x);
diff --git a/makefiles/Makefile.in b/makefiles/Makefile.in
index f780585820..4b4abe338c 100644
--- a/makefiles/Makefile.in
+++ b/makefiles/Makefile.in
@@ -32,7 +32,6 @@ clean:
 
 distclean:
 	rm -rf $(workarea)
-	rm -rf nanopass
-	rm -rf zlib
+	(cd zlib ; make distclean)
 	rm -f Makefile
 	rm -f Make.out
diff --git a/s/mkheader.ss b/s/mkheader.ss
index 04b6444996..0a45118507 100644
--- a/s/mkheader.ss
+++ b/s/mkheader.ss
@@ -310,7 +310,7 @@
         (export "void" "Svector_set" "(ptr, iptr, ptr)")
   
         (nl) (comment "Constructors")
-        (def "Sfixnum(x)" (format "((ptr)(uptr)((x)<<~d))" ($ fixnum-offset)))
+        (def "Sfixnum(x)" (format "((ptr)(uptr)((x)*~d))" ($ fixnum-factor)))
         (def "Schar(x)"
           (format "((ptr)(uptr)((x)<<~d|0x~x))"
             ($ char-data-offset)