Declare __fake_use_va_args as a constexpr function.
* Need a body and return value for this function
so the constexpr check can inline it.
* C mode can just use an extern function declaration, but not constexpr.
Bug: 116854606
Bug: 111614304
Test: build with WITH_TIDY=1 and enable static analyzer checks
Change-Id: Ie3f4efbcabed99416d196b6c361a772b8c6a4035
diff --git a/liblog/include/log/log_main.h b/liblog/include/log/log_main.h
index e7b1728..53653de 100644
--- a/liblog/include/log/log_main.h
+++ b/liblog/include/log/log_main.h
@@ -56,15 +56,24 @@
/*
* Use __VA_ARGS__ if running a static analyzer,
* to avoid warnings of unused variables in __VA_ARGS__.
- * __FAKE_USE_VA_ARGS is undefined at link time,
- * so don't link with __clang_analyzer__ defined.
+ * Use contexpr function in C++ mode, so these macros can be used
+ * in other constexpr functions without warning.
*/
#ifdef __clang_analyzer__
-extern void __fake_use_va_args(int, ...);
-#define __FAKE_USE_VA_ARGS(...) __fake_use_va_args(0, ##__VA_ARGS__)
+#ifdef __cplusplus
+extern "C++" {
+template <typename... Ts>
+constexpr int __fake_use_va_args(Ts...) {
+ return 0;
+}
+}
+#else
+extern int __fake_use_va_args(int, ...);
+#endif /* __cplusplus */
+#define __FAKE_USE_VA_ARGS(...) ((void)__fake_use_va_args(0, ##__VA_ARGS__))
#else
#define __FAKE_USE_VA_ARGS(...) ((void)(0))
-#endif
+#endif /* __clang_analyzer__ */
#ifndef __predict_false
#define __predict_false(exp) __builtin_expect((exp) != 0, 0)
