[Bug ada/30618] New: Infinite loop in sem_ch8.end_use_clauses

[ludovic at ludovic-brenta dot org]

This is Debian bug #408703; see the attached files that reproduce
the problem.  The command line is

gnatmake integer_indexed_io-debug.ads

After successfully compiling a couple of files, gnat1 then goes into
an infinite loop while parsing integer_indexed_io-debug.ads.  The
backtrace I got when running "gnat1 integer_indexed_io-debug.ads"
under gdb and hitting Ctrl+C says:

#1  0x00000000005b0cc0 in sem_ch8.end_use_clauses ()
#2  0x00000000005b0e4d in sem_ch8.pop_scope ()
#3  0x0000000000560b4a in sem_ch10.remove_parents ()
#4  0x0000000000560c19 in sem_ch10.remove_context ()
#5  0x00000000005664f2 in sem_ch10.analyze_compilation_unit ()
#6  0x000000000054b4ac in sem.analyze ()
#7  0x000000000054b829 in sem.semantics.do_analyze ()
#8  0x000000000054ba66 in sem.semantics ()
#9  0x00000000004f1a30 in frontend ()
#10 0x000000000062bac6 in gnat1drv ()
#11 0x0000000000412dad in gnat_parse_file ()
#12 0x0000000000870138 in toplev_main ()
#13 0x00002ade5132c4ca in __libc_start_main () from /lib/libc.so.6
#14 0x0000000000402f0a in _start () at ../sysdeps/x86_64/elf/start.S:113

If you stop gnat1 at various times, the topmost frame (#0)
varies, but after executing the statements until you return to
sem_ch8.end_use_clauses and type n, the infinite loop resumes.

Memory usage remains constant in the infinite loop.

-- 
Ludovic Brenta.


-- 
           Summary: Infinite loop in sem_ch8.end_use_clauses
           Product: gcc
           Version: 4.1.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: ada
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: ludovic at ludovic-brenta dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30618