Add missing dump_file check

[Jan Hubicka via Gcc-patches]

Hi,
I forgot to check dump_file being non-NULL before writting to it.
It is somewhat odd that this does not trigger more often - I will take
deeper look tomorrow, but I am checking this in as obvious to avoid ICE.

Honza

gcc/ChangeLog:

        PR tree-optimization/110600
        * cfgloopmanip.cc (scale_loop_profile): Add mising profile_dump check.

gcc/testsuite/ChangeLog:

        PR tree-optimization/110600
        * gcc.c-torture/compile/pr110600.c: New test.

diff --git a/gcc/cfgloopmanip.cc b/gcc/cfgloopmanip.cc
index 52732420787..5c0065b2f5a 100644
--- a/gcc/cfgloopmanip.cc
+++ b/gcc/cfgloopmanip.cc
@@ -582,9 +582,10 @@ scale_loop_profile (class loop *loop, profile_probability 
p,
 
   if (exit_edge && exit_edge->src->loop_father != loop)
     {
-      fprintf (dump_file,
-              ";; Loop exit is in inner loop;"
-              " will leave exit probabilities inconsistent\n");
+      if (dump_file && (dump_flags & TDF_DETAILS))
+       fprintf (dump_file,
+                ";; Loop exit is in inner loop;"
+                " will leave exit probabilities inconsistent\n");
     }
   else if (exit_edge)
     {
diff --git a/gcc/testsuite/gcc.c-torture/compile/pr110600.c 
b/gcc/testsuite/gcc.c-torture/compile/pr110600.c
new file mode 100644
index 00000000000..4b126f74e43
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr110600.c
@@ -0,0 +1,6 @@
+int a(int b, int c) { return (b ^ c) < 0 ? b : b - c; }
+int main() {
+  for (int e = 0; e != -1; e = a(e, 1))
+    ;
+  return 0;
+}