bpo-36254: Fix invalid uses of %d in format strings in C. (GH-12264)

diff --git a/PC/launcher.c b/PC/launcher.c
index a4e6781..0f5003a 100644
--- a/PC/launcher.c
+++ b/PC/launcher.c
@@ -718,7 +718,7 @@
         }
         child_command = calloc(child_command_size, sizeof(wchar_t));
         if (child_command == NULL)
-            error(RC_CREATE_PROCESS, L"unable to allocate %d bytes for child command.",
+            error(RC_CREATE_PROCESS, L"unable to allocate %zd bytes for child command.",
                   child_command_size);
         if (no_suffix)
             _snwprintf_s(child_command, child_command_size,
@@ -1189,7 +1189,7 @@
 
     if (rc == 0) {
         read = fread(buffer, sizeof(char), BUFSIZE, fp);
-        debug(L"maybe_handle_shebang: read %d bytes\n", read);
+        debug(L"maybe_handle_shebang: read %zd bytes\n", read);
         fclose(fp);
 
         if ((read >= 4) && (buffer[3] == '\n') && (buffer[2] == '\r')) {
@@ -1209,7 +1209,7 @@
             bom = BOMs; /* points to UTF-8 entry - the default */
         }
         else {
-            debug(L"maybe_handle_shebang: BOM found, code page %d\n",
+            debug(L"maybe_handle_shebang: BOM found, code page %u\n",
                   bom->code_page);
             start = &buffer[bom->length];
         }