diff --git a/src/p_exe.cpp b/src/p_exe.cpp
index 13fdee31..00586be9 100644
--- a/src/p_exe.cpp
+++ b/src/p_exe.cpp
@@ -338,7 +338,7 @@ unsigned optimize_relocs(upx_byte *b, const unsigned size,
     set_le16 (crel_save+2,seg_high);
 
     //OutputFile::dump("x.rel", crel_save, crel - crel_save);
-    return crel - crel_save;
+    return (unsigned) (crel - crel_save);
 }
 
 
@@ -605,12 +605,11 @@ void PackExe::unpack(OutputFile *fo)
     {
         relocs -= get_le16(obuf+ph.u_len-2);
         ph.u_len -= 2;
-        upx_byte *p;
 
         wrkmem.alloc(4*MAXRELOCS);
-        unsigned es = 0,ones = get_le16(relocs);
-        unsigned seghi = get_le16(relocs+2);
-        p = relocs + 4;
+        unsigned es = 0, ones = get_le16(relocs);
+        const unsigned seghi = get_le16(relocs+2);
+        const upx_byte *p = relocs + 4;
 
         while (ones)
         {
@@ -628,10 +627,10 @@ void PackExe::unpack(OutputFile *fo)
                 dorel = true;
                 if (*p == 0)
                 {
-                    upx_byte *q;
+                    const upx_byte *q;
                     for (q = obuf+es*16+di; !(*q == 0x9a && get_le16(q+3) <= seghi); q++)
                         ;
-                    di = q - (obuf+es*16) + 3;
+                    di = ptr_diff(q, obuf+es*16) + 3;
                 }
                 else if (*p == 1)
                 {
diff --git a/src/p_w32pe.cpp b/src/p_w32pe.cpp
index 30c18b49..def39cd6 100644
--- a/src/p_w32pe.cpp
+++ b/src/p_w32pe.cpp
@@ -66,6 +66,18 @@ static const
 #  define strcpy(a,b)   strcpy((char *)(a),(const char *)(b))
 #endif
 
+#if 1
+static unsigned my_strlen(const char *s)
+{
+    size_t l = strlen((const char*)s); assert((unsigned) l == l); return (unsigned) l;
+}
+static unsigned my_strlen(const unsigned char *s)
+{
+    size_t l = strlen((const char*)s); assert((unsigned) l == l); return (unsigned) l;
+}
+#define strlen my_strlen
+#endif
+
 
 // Unicode string compare
 static bool ustrsame(const void *s1, const void *s2)
@@ -728,11 +740,11 @@ unsigned PackW32Pe::processImports() // pass 1
             }
         ppi++;
 
-        unsigned esize = ptr_diff(tarr,idlls[ic]->lookupt);
+        unsigned esize = ptr_diff((char *)tarr, (char *)idlls[ic]->lookupt);
         lookups.add(idlls[ic]->lookupt,esize);
-        if (ptr_diff(ibuf + idlls[ic]->iat,idlls[ic]->lookupt))
+        if (ptr_diff(ibuf + idlls[ic]->iat, (char *)idlls[ic]->lookupt))
         {
-            memcpy(ibuf + idlls[ic]->iat,idlls[ic]->lookupt,esize);
+            memcpy(ibuf + idlls[ic]->iat, idlls[ic]->lookupt, esize);
             iats.add(idlls[ic]->iat,esize);
         }
         names.add(idlls[ic]->name,strlen(idlls[ic]->name) + 1 + 1);
@@ -908,26 +920,26 @@ void Export::convert(unsigned eoffs,unsigned esize)
 #endif
 }
 
-void Export::build(char *newbase,unsigned newoffs)
+void Export::build(char *newbase, unsigned newoffs)
 {
-    char *functionp = newbase + sizeof(edir);
-    char *namep = functionp + 4 * edir.functions;
-    char *ordinalp = namep + 4 * edir.names;
-    char *enamep = ordinalp + 2 * edir.names;
-    char *exports = enamep + strlen(ename) + 1;
+    char * const functionp = newbase + sizeof(edir);
+    char * const namep = functionp + 4 * edir.functions;
+    char * const ordinalp = namep + 4 * edir.names;
+    char * const enamep = ordinalp + 2 * edir.names;
+    char * exports = enamep + strlen(ename) + 1;
 
-    edir.addrtable = newoffs + functionp - newbase;
-    edir.ordinaltable = newoffs + ordinalp - newbase;
+    edir.addrtable = newoffs + ptr_diff(functionp, newbase);
+    edir.ordinaltable = newoffs + ptr_diff(ordinalp, newbase);
     memcpy(ordinalp,ordinals,2 * edir.names);
 
-    edir.name = newoffs + enamep - newbase;
+    edir.name = newoffs + ptr_diff(enamep, newbase);
     strcpy(enamep,ename);
-    edir.nameptrtable = newoffs + namep - newbase;
+    edir.nameptrtable = newoffs + ptr_diff(namep, newbase);
     unsigned ic;
     for (ic = 0; ic < edir.names; ic++)
     {
         strcpy(exports,names[ic]);
-        set_le32(namep + 4 * ic,newoffs + exports - newbase);
+        set_le32(namep + 4 * ic,newoffs + ptr_diff(exports, newbase));
         exports += strlen(exports) + 1;
     }
 
@@ -936,7 +948,7 @@ void Export::build(char *newbase,unsigned newoffs)
         if (names[edir.names + ic])
         {
             strcpy(exports,names[edir.names + ic]);
-            set_le32(functionp + 4 * ic,newoffs + exports - newbase);
+            set_le32(functionp + 4 * ic,newoffs + ptr_diff(exports, newbase));
             exports += strlen(exports) + 1;
         }
 
diff --git a/src/p_wcle.cpp b/src/p_wcle.cpp
index 4bcc603b..51dd47de 100644
--- a/src/p_wcle.cpp
+++ b/src/p_wcle.cpp
@@ -166,7 +166,7 @@ void PackWcle::encodeEntryTable()
     //if (Opt_debug) printf("%d entries encoded.\n",n);
     UNUSED(n);
 
-    soentries = p - ientries + 1;
+    soentries = ptr_diff(p, ientries) + 1;
     oentries = ientries;
     ientries = NULL;
 }
@@ -402,7 +402,7 @@ void PackWcle::preprocessFixups()
     set_le32(fix,0xFFFFFFFFUL);
     fix += 4;
 
-    sofixups = fix - ifixups;
+    sofixups = ptr_diff(fix, ifixups);
 }
 
 
@@ -590,7 +590,7 @@ void PackWcle::decodeFixups()
     while (*selfrel_fixups != 0xC3)
         selfrel_fixups += 9;
     selfrel_fixups++;
-    unsigned selectlen = (selfrel_fixups - selector_fixups)/9;
+    unsigned selectlen = ptr_diff(selfrel_fixups, selector_fixups)/9;
 
     ofixups = new upx_byte[fixupn*9+1000+selectlen*5];
     upx_bytep fp = ofixups;
@@ -656,11 +656,11 @@ void PackWcle::decodeFixups()
             fp += fp[1] ? 9 : 7;
             jc += 2;
         }
-        set_le32(ofpage_table+ic,fp-ofixups);
+        set_le32(ofpage_table+ic,ptr_diff(fp,ofixups));
     }
     for (ic=0; ic < FIXUP_EXTRA; ic++)
         *fp++ = 0;
-    sofixups = fp-ofixups;
+    sofixups = ptr_diff(fp, ofixups);
 }
 
 
@@ -748,7 +748,7 @@ void PackWcle::decodeEntryTable()
 
     //if (Opt_debug) printf("\n%d entries decoded.\n",n);
 
-    soentries = p - ientries + 1;
+    soentries = ptr_diff(p, ientries) + 1;
     oentries = ientries;
     ientries = NULL;
 }