From ff3d3f01025b881c7cadf093b0f65309c35f2c53 Mon Sep 17 00:00:00 2001
From: Mark Wooding <mdw@distorted.org.uk>
Date: Wed, 5 Jul 2017 21:25:31 +0100
Subject: [PATCH] utils/macros.h: Add support for Clang-specific hacks.

These are mostly the same as GCC, but (fortunately!) Clang's diagnostics
handling is less broken than GCC's, so we can do the same job much more
simply.
---
 utils/macros.h | 37 +++++++++++++++++++++++++++++++++----
 1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/utils/macros.h b/utils/macros.h
index 35ececf..02d820e 100644
--- a/utils/macros.h
+++ b/utils/macros.h
@@ -53,24 +53,49 @@
 #  define GCC_VERSION_P(maj, min) 0
 #endif
 
-#if GCC_VERSION_P(2, 5)
+#ifdef __clang__
+#  define CLANG_VERSION_P(maj, min)					\
+	(__clang_major__ > (maj) || (__clang_major__ == (maj) &&	\
+				     __clang_minor__ >= (min)))
+#else
+#  define CLANG_VERSION_P(maj, min) 0
+#endif
+
+#if GCC_VERSION_P(2, 5) || CLANG_VERSION_P(3, 3)
 #  define NORETURN __attribute__((noreturn))
 #  define PRINTF_LIKE(fix, aix) __attribute__((format(printf, fix, aix)))
 #  define SCANF_LIKE(fix, aix) __attribute__((format(scanf, fix, aix)))
 #  define IGNORABLE __attribute__((unused))
 #endif
 
-#if GCC_VERSION_P(4, 5)
+#if GCC_VERSION_P(4, 5) || CLANG_VERSION_P(3, 3)
 #  define DEPRECATED(msg) __attribute__((deprecated(msg)))
 #elif GCC_VERSION_P(3, 1)
 #  define DEPRECATED(msg) __attribute__((deprecated))
 #endif
 
-#if GCC_VERSION_P(4, 0)
+#if GCC_VERSION_P(4, 0) || CLANG_VERSION_P(3, 3)
 #  define EXECL_LIKE(ntrail) __attribute__((sentinel(ntrail)))
 #endif
 
-#if GCC_VERSION_P(4, 6)
+#if CLANG_VERSION_P(3, 3)
+
+#  define MLIB__PRAGMA_HACK(x) _Pragma(#x)
+#  define MLIB__MUFFLE_WARNINGS(warns, body)				\
+	_Pragma("clang diagnostic push")				\
+	warns								\
+	body								\
+	_Pragma("clang diagnostic pop")
+#  define CLANG_WARNING(warn)						\
+	MLIB__PRAGMA_HACK(clang diagnostic ignored warn)
+#  define MUFFLE_WARNINGS_DECL(warns, body)				\
+	MLIB__MUFFLE_WARNINGS(warns, body)
+#  define MUFFLE_WARNINGS_EXPR(warns, body)				\
+	__extension__ ({ MLIB__MUFFLE_WARNINGS(warns, (body);) })
+#  define MUFFLE_WARNINGS_STMT(warns, body)				\
+	do { MLIB__MUFFLE_WARNINGS(warns, body) } while (0)
+
+#elif GCC_VERSION_P(4, 6)
 
    /* --- Diagnostic suppression in GCC: a tale of woe --- *
     *
@@ -172,6 +197,10 @@
 #  define GCC_WARNING(warn)
 #endif
 
+#ifndef CLANG_WARNING
+#  define CLANG_WARNING(warn)
+#endif
+
 /*----- That's all, folks -------------------------------------------------*/
 
 #ifdef __cplusplus
-- 
2.11.0