Created attachment 10488 [details]
Test case demonstrating problem with printing all variables in scope in OpenMP program

When a breakpoint is placed within a parallel region within an OpenMP program, GDB is unable to print variables which are in scope, but which are not referenced within the parallel region.

I've attached an example which I intend to use as a test which I plan to post to gdb-patches.  (I'm filing this bug so I have a bug id to use for tests which I need to kfail.)

This program can be compiled with the following command:

gcc -o omp-par-scope -g -fopenmp omp-par-scope.c

Debugging it in gdb and placing a breakpoint on the first printf (on line 39) and running to that breakpoint reveals that variable i3 cannot be printed...

(gdb) b 39
Breakpoint 1 at 0x400b20: file omp-par-scope.c, line 39.
(gdb) run
Starting program: omp-par-scope 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
[New Thread 0x7ffff73d6700 (LWP 8483)]

Breakpoint 1, single_scope._omp_fn.0 () at omp-par-scope.c:39
39          printf ("single_scope: thread_num=%d, s1=%d, i1=%d, s2=%d, i2=%d\n",
(gdb) print i3
No symbol "i3" in current context.

This is what it looks like when it works correctly:

(gdb) b 39
Breakpoint 1 at 0x400a6a: file omp-par-scope.c, line 39.
(gdb) run
Starting program: /mesquite2/sourceware-git/binutils-gdb/gdb/testsuite/gdb.threads/omp-par-scope 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
[New Thread 0x7ffff73cb700 (LWP 8504)]
[Switching to Thread 0x7ffff73cb700 (LWP 8504)]

Thread 2 "omp-par-scope" hit Breakpoint 1, single_scope._omp_fn.0 () at omp-par-scope.c:39
39          printf ("single_scope: thread_num=%d, s1=%d, i1=%d, s2=%d, i2=%d\n",
(gdb) print i3
$1 = 13

Moreover, continuing to the breakpoint again in the second/other thread should also correctly print i3:

(gdb) c
Continuing.
single_scope: thread_num=1, s1=-41, i1=11, s2=202, i2=212
[Switching to Thread 0x7ffff7fd9780 (LWP 8500)]

Thread 1 "omp-par-scope" hit Breakpoint 1, single_scope._omp_fn.0 () at omp-par-scope.c:39
39          printf ("single_scope: thread_num=%d, s1=%d, i1=%d, s2=%d, i2=%d\n",
(gdb) print i3
$2 = 13