https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64042
--- Comment #5 from vries at gcc dot gnu.org ---
An easy way to reproduce, is to add this patch:
...
diff -u
/home/vries/gcc_versions/data/ref-master-14-12-02/src/boehm-gc/testsuite/boehm-gc.c/c.exp
./c.exp
---
/home/vries/gcc_versions/data/ref-master-14-12-02/src/boehm-gc/testsuite/boehm-gc.c/c.exp
2014-12-02 02:51:25.000000000 +0100
+++ ./c.exp 2014-11-26 14:39:41.964962842 +0100
@@ -19,4 +19,8 @@
boehm-gc-dg-runtest [lsort [glob -nocomplain $srcdir/$subdir/*.c]] "-O2" ""
+for {set i 0} {$i < 1000} {incr i} {
+ boehm-gc-dg-runtest [lsort [glob -nocomplain $srcdir/$subdir/gctest.c]]
"-O2" ""
+}
+
dg-finish
...
This way (1000 * compile/run) it triggered twice for me.
