PR10746: improve error message on utrace-less kernels

* tapset-itrace.exp (itrace_derived_probe ctor): Fail if !CONFIG_UTRACE.
* tapset-utrace.exp (utrace_derived_probe ctor): Fail if !CONFIG_UTRACE.
* tapsets.cxx (dwarf_builder::build): Fail process.* if !CONFIG_UTRACE.
* testsuite/semko/utrace.stp: New test.

1 files changed, 3 insertions, 0 deletions

diff --git a/testsuite/semko/utrace.stp b/testsuite/semko/utrace.stp
new file mode 100755
index 00000000..5cc649e9
--- /dev/null
+++ b/testsuite/semko/utrace.stp
@@ -0,0 +1,3 @@
+#! stap -p2
+
+probe   %( CONFIG_UTRACE != "y" %? process.begin %: never %)    { }