Silence GCC's "cast of pointer to integer of a different size" warning

When calculating hashes from pointers, it actually makes sense to cut
off the most significant bits. In that case, said warning does not make
a whole lot of sense.

So let's just work around it by casting the pointer first to intptr_t
and then casting up/down to the final integral type.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

compat/regex/regcomp.c

@@ -18,6 +18,8 @@
    Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301 USA.  */
 
+#include <stdint.h>
+
 static reg_errcode_t re_compile_internal (regex_t *preg, const char * pattern,
 					  size_t length, reg_syntax_t syntax);
 static void re_compile_fastmap_iter (regex_t *bufp,
@@ -2577,7 +2579,7 @@ parse_dup_op (bin_tree_t *elem, re_string_t *regexp, re_dfa_t *dfa,
     old_tree = NULL;
 
   if (elem->token.type == SUBEXP)
-    postorder (elem, mark_opt_subexp, (void *) (long) elem->token.opr.idx);
+    postorder (elem, mark_opt_subexp, (void *) (intptr_t) elem->token.opr.idx);
 
   tree = create_tree (dfa, elem, NULL, (end == -1 ? OP_DUP_ASTERISK : OP_ALT));
   if (BE (tree == NULL, 0))
@@ -3806,7 +3808,7 @@ create_token_tree (re_dfa_t *dfa, bin_tree_t *left, bin_tree_t *right,
 static reg_errcode_t
 mark_opt_subexp (void *extra, bin_tree_t *node)
 {
-  int idx = (int) (long) extra;
+  int idx = (int) (intptr_t) extra;
   if (node->token.type == SUBEXP && node->token.opr.idx == idx)
     node->token.opt_subexp = 1;
 

pack-revindex.c

@@ -21,7 +21,7 @@ static int pack_revindex_hashsz;
 
 static int pack_revindex_ix(struct packed_git *p)
 {
-	unsigned long ui = (unsigned long)p;
+	unsigned long ui = (unsigned long)(intptr_t)p;
 	int i;
 
 	ui = ui ^ (ui >> 16); /* defeat structure alignment */

sha1_file.c

@@ -2014,7 +2014,7 @@ static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset)
 {
 	unsigned long hash;
 
-	hash = (unsigned long)p + (unsigned long)base_offset;
+	hash = (unsigned long)(intptr_t)p + (unsigned long)base_offset;
 	hash += (hash >> 8) + (hash >> 16);
 	return hash % MAX_DELTA_CACHE;
 }