revert r66768 for Ruby 2.7 due to Misc#15347

It's safer to backport r66768 to 2.6 branch, but for 2.7 it's not
needed anymore.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66782 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

addr2line.c

@@ -1193,7 +1193,6 @@ debug_info_reader_read_value(DebugInfoReader *reader, uint64_t form, DebugInfoVa
 static char *
 di_find_abbrev(DebugInfoReader *reader, uint64_t abbrev_number)
 {
-    uint64_t n;
     char *p;
     if (abbrev_number < ABBREV_TABLE_SIZE) {
         return reader->abbrev_table[abbrev_number];
@@ -1208,7 +1207,7 @@ di_find_abbrev(DebugInfoReader *reader, uint64_t abbrev_number)
         uint64_t form = uleb128(&p);
         if (!at && !form) break;
     }
-    for (n = uleb128(&p); abbrev_number != n; n = uleb128(&p)) {
+    for (uint64_t n = uleb128(&p); abbrev_number != n; n = uleb128(&p)) {
         if (n == 0) {
             fprintf(stderr,"%d: Abbrev Number %"PRId64" not found\n",__LINE__, abbrev_number);
             exit(1);
@@ -1507,9 +1506,7 @@ read_abstract_origin(DebugInfoReader *reader, uint64_t abstract_origin, line_inf
 
 static void
 debug_info_read(DebugInfoReader *reader, int num_traces, void **traces,
-         line_info_t *lines, int offset)
-{
-    int i;
+         line_info_t *lines, int offset) {
     while (reader->p < reader->cu_end) {
         DIE die;
         ranges_t ranges = {};
@@ -1558,7 +1555,7 @@ debug_info_read(DebugInfoReader *reader, int num_traces, void **traces,
         }
         /* ranges_inspect(reader, &ranges); */
         /* fprintf(stderr,"%d:%tx: %x ",__LINE__,diepos,die.tag); */
-        for (i=offset; i < num_traces; i++) {
+        for (int i=offset; i < num_traces; i++) {
             uintptr_t addr = (uintptr_t)traces[i];
             uintptr_t offset = addr - reader->obj->base_addr + reader->obj->vmaddr;
             uintptr_t saddr = ranges_include(reader, &ranges, offset);