different behavior when remote debugger is used
Description of problem:
I found Qemu shows different behavior when I run Qemu with hello-world (statically linked binary enclosed) directly or run it through remote debugger. I need help to understand the following: 

1. Is this intended behavior?
1. Any way to make the two approaches have consistent behavior (I prefer the behavior shown in the 2nd approach described below)
1. If it is intended behavior, any explanation why or suggestions how to dig further to root cause the difference.

The corresponding source code is the line 86 in [filedoalloc.c](https://code.woboq.org/userspace/glibc/libio/filedoalloc.c.html#86). It tests if the file (stdout) is char special device (S_ISCHR)
The preprocessed code is as follows:
   if (((((st.st_mode)) & 0170000) == (0020000))) 

I then compared two different approaches to run Qemu:

1. I used the following command line to collect the trace:  qemu_aarch64 -strace  -plugin $QEMU_ROOT/build/contrib/plugins/libexeclog.so -d plugin hello.a64. This one tests False for S_ISCHR
1. when I used gdb to connect to Qemu and single-step the instructions, S_ISCHR tests True, which is different from running qemu directly (approach 1). 

Thanks!
Steps to reproduce:
1.[hello.a64](/uploads/4b4ccae8c1e4b045c39ceae6a094d55a/hello.a64)
2.
3.
Additional information: