extern "C" {
#endif
-/*----- Macros provided ---------------------------------------------------*/
+/*----- Miscellaneous utility macros --------------------------------------*/
#define N(v) (sizeof(v)/sizeof(*v))
#define MLIB__GLUE(x, y) x##y
#define GLUE(x, y) MLIB__GLUE(x, y)
+/*----- Compiler diagnostics ----------------------------------------------*/
+
+/* --- Compiler-specific definitions --- */
+
+#if defined(__GNUC__)
+
+# define GCC_VERSION_P(maj, min) \
+ (__GNUC__ > (maj) || (__GNUC__ == (maj) && __GNUC_MINOR__ >= (min)))
+
+# if GCC_VERSION_P(2, 5)
+# 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)
+# define DEPRECATED(msg) __attribute__((deprecated(msg)))
+# elif GCC_VERSION_P(3, 1)
+# define DEPRECATED(msg) __attribute__((deprecated))
+# endif
+
+# if GCC_VERSION_P(4, 0)
+# define EXECL_LIKE(ntrail) __attribute__((sentinel(ntrail)))
+# endif
+
+# if GCC_VERSION_P(4, 6)
+
+ /* --- Diagnostic suppression in GCC: a tale of woe --- *
+ *
+ * This is extremely unpleasant, largely as a result of bugs in the GCC
+ * preprocessor's handling of @_Pragma@. The fundamental problem is
+ * that it's the preprocessor, and not the compiler proper, which
+ * detects @_Pragma@, emitting @#pragma@ lines into its output; and it
+ * does it during macro expansion, even if the macro is being expanded
+ * during argument collection. Since arguments are expanded before
+ * replacing the macro's invocation with its body, a pragma in an
+ * argument will be emitted %%\emph{before}%% any pragmata in the body,
+ * even if they appear before the argument in the body -- and even if
+ * the argument doesn't actually appear anywhere at all in the body.
+ *
+ * Another, rather less significant, problem is that @_Pragma@'s
+ * argument is a single string literal, recognized in translation phase
+ * 4, before string-literal concatenation in phase 6, so we must build
+ * pragma bodies as token lists and then stringify them.
+ *
+ * As a result, we need some subterfuge here. The @MLIB__PRAGMA_HACK@
+ * macro issues a @_Pragma@ on its argument token list, which it
+ * stringifies; this deals with the second problem. The first is
+ * trickier: we must delay expansion of @MLIB__PRAGMA_HACK@ from the
+ * argument collection phase to the body rescanning phase, and we do
+ * this by splitting the invocations between @GCC_WARNING@ macro calls:
+ * the name is left hanging from the previous call (or from
+ * @MLIB__MUFFLE_WARNINGS@, in the first case) and the body is supplied
+ * by @GCC_WARNING@, which also supplies the next @MLIB__PRAGMA_HACK@.
+ * The remaining problem is to make sure we can dispose of the final
+ * trailing @MLIB__PRAGMA_HACK@ harmlessly, which we do by introducing
+ * an extra argument @emitp@, which may be either @t@ or @nil@; this
+ * dispatches to an appropriate helper macro by means of token-pasting.
+ *
+ * I'm so sorry.
+ */
+
+# define MLIB__PRAGMA_HACK_t(x) _Pragma(#x)
+# define MLIB__PRAGMA_HACK_nil(x)
+# define MLIB__PRAGMA_HACK(emitp, x) MLIB__PRAGMA_HACK_##emitp(x)
+# define MLIB__MUFFLE_WARNINGS(warns, body) \
+ _Pragma("GCC diagnostic push") MLIB__PRAGMA_HACK \
+ warns \
+ (nil, nil) \
+ body \
+ _Pragma("GCC diagnostic pop")
+# define GCC_WARNING(warn) \
+ (t, GCC diagnostic ignored warn) MLIB__PRAGMA_HACK
+# 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)
+# endif
+
+#endif
+
+/* --- Fallback definitions, mostly trivial --- */
+
+#ifndef GCC_VERSION_P
+# define GCC_VERSION_P(maj, min) 0
+#endif
+
+#ifndef DEPRECATED
+# define DEPRECATED(msg)
+#endif
+
+#ifndef EXECL_LIKE
+# define EXECL_LIKE(ntrail)
+#endif
+
+#ifndef DISCARD
+# define DISCARD(x) do if (x); while (0)
+#endif
+
+#ifndef IGNORE
+# define IGNORE(x) ((void)(x))
+#endif
+
+#ifndef MUFFLE_WARNINGS_DECL
+# define MUFFLE_WARNINGS_DECL(warns, body) body
+#endif
+
+#ifndef MUFFLE_WARNINGS_EXPR
+# define MUFFLE_WARNINGS_EXPR(warns, body) (body)
+#endif
+
+#ifndef MUFFLE_WARNINGS_STMT
+# define MUFFLE_WARNINGS_STMT(warns, body) do { body } while (0)
+#endif
+
+#ifndef PRINTF_LIKE
+# define PRINF_LIKE(fmtix, argix)
+#endif
+
+#ifndef SCANF_LIKE
+# define SCANF_LIKE(fmtix, argix)
+#endif
+
+#ifndef IGNORABLE
+# define IGNORABLE
+#endif
+
+#ifndef GCC_WARNING
+# define GCC_WARNING(warn)
+#endif
+
/*----- That's all, folks -------------------------------------------------*/
#ifdef __cplusplus
~mdw / mLib / blobdiff