xsm: add bodge when compiling with llvm coverage support

llvm coverage support seems to disable some of the optimizations
needed in order to compile xsm, and the end result is that references
to __xsm_action_mismatch_detected are left in the object files.

Since coverage support cannot be used in production, introduce
__xsm_action_mismatch_detected for llvm coverage builds.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>

diff --git a/xen/include/xsm/dummy.h b/xen/include/xsm/dummy.h
index d6ddadcafdc09240760c2a5dd40677a31c879da8..466bbcbde8d5e814e08896cbac39814c14411dd2 100644 (file)
--- a/xen/include/xsm/dummy.h
+++ b/xen/include/xsm/dummy.h
@@ -24,8 +24,22 @@
  * if references remain at link time.
  */
 #define LINKER_BUG_ON(x) do { if (x) __xsm_action_mismatch_detected(); } while (0)
+
+#if defined(CONFIG_COVERAGE) && defined(__clang__)
+/*
+ * LLVM coverage support seems to disable some of the optimizations needed in
+ * order for XSM to compile. Since coverage should not be used in production
+ * provide an implementation of __xsm_action_mismatch_detected to satisfy the
+ * linker.
+ */
+static inline void __xsm_action_mismatch_detected(void)
+{
+    ASSERT_UNREACHABLE();
+}
+#else
 /* DO NOT implement this function; it is supposed to trigger link errors */
 void __xsm_action_mismatch_detected(void);
+#endif
 
 #ifdef CONFIG_XSM