O_EXCL has no meaning for fdopen

"exclusive access mode is not supported" exception has resulted in
empty "rubyheap-*.json" files after test/objspace/test_objspace.rb.

1 files changed, 1 insertions, 1 deletions

diff --git a/io.c b/io.c
index 0db981e39c..5e04da806b 100644
--- a/io.c
+++ b/io.c
@@ -8037,7 +8037,7 @@ FILE *
 rb_io_stdio_file(rb_io_t *fptr)
 {
     if (!fptr->stdio_file) {
-        int oflags = rb_io_fmode_oflags(fptr->mode);
+        int oflags = rb_io_fmode_oflags(fptr->mode) & ~O_EXCL;
         fptr->stdio_file = rb_fdopen(fptr->fd, rb_io_oflags_modestr(oflags));
     }
     return fptr->stdio_file;