[Bug target/47955] New: gcc.dg/stack-usage-1.c fails on m68k-linux

["mikpe at it dot uu.se" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47955

           Summary: gcc.dg/stack-usage-1.c fails on m68k-linux
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: mikpe@it.uu.se


The gcc.dg/stack-usage-1.c test case fails on m68k-linux:

> fgrep stack-usage- gcc/testsuite/gcc/gcc.log 
Executing on host: /mnt/scratch/objdir46/gcc/xgcc -B/mnt/scratch/objdir46/gcc/
/mnt/scratch/gcc-4.6-20110226/gcc/testsuite/gcc.dg/stack-usage-1.c  
-fstack-usage -S  -o stack-usage-1.s    (timeout = 300)
/mnt/scratch/gcc-4.6-20110226/gcc/testsuite/gcc.dg/stack-usage-1.c: In function
'foo':
/mnt/scratch/gcc-4.6-20110226/gcc/testsuite/gcc.dg/stack-usage-1.c:53:1:
warning: -fstack-usage not supported for this target [enabled by default]
/mnt/scratch/gcc-4.6-20110226/gcc/testsuite/gcc.dg/stack-usage-1.c: In function
'foo':
/mnt/scratch/gcc-4.6-20110226/gcc/testsuite/gcc.dg/stack-usage-1.c:53:1:
warning: -fstack-usage not supported for this target [enabled by default]
FAIL: gcc.dg/stack-usage-1.c (test for excess errors)
/mnt/scratch/gcc-4.6-20110226/gcc/testsuite/gcc.dg/stack-usage-1.c:53:1:
warning: -fstack-usage not supported for this target [enabled by default]
FAIL: gcc.dg/stack-usage-1.c scan-file foo\t(256|264)\tstatic

The issue is that the m68k backend doesn't set stack usage data, which generic
parts detect and report as "-fstack-usage not supported".

m68k_expand_prologue() should update current_function_static_stack_size if
flag_stack_usage is set.