IMPORT: slz: define and use a __fallthrough statement for switch/case
When the code is preprocessed first and compiled later, such as when
built under distcc, the "fall through" comments are dropped and warnings
are emitted. Let's use the alternative "fallthrough" attribute instead,
that is supported by versions of gcc and clang that also produce this
warning.
This is libslz upstream commit 0fdf8ae218f3ecb0b7f22afd1a6b35a4f94053e2
diff --git a/include/import/slz-tables.h b/include/import/slz-tables.h
index 8e8b679..0b3a5b9 100644
--- a/include/import/slz-tables.h
+++ b/include/import/slz-tables.h
@@ -124,6 +124,23 @@
0x0d1d23, 0x0d1e23, 0x0800a3 /* 256-258 */
};
+/* This horrible mess is needed to shut up the fallthrough warning since the
+ * stupid comment approach doesn't resist to separate preprocessing (e.g. as
+ * used in distcc). Note that compilers which support the fallthrough attribute
+ * also support __has_attribute.
+ */
+#ifndef __fallthrough
+# ifdef __has_attribute
+# if __has_attribute(fallthrough)
+# define __fallthrough __attribute__((fallthrough))
+# else
+# define __fallthrough do { } while (0)
+# endif
+# else
+# define __fallthrough do { } while (0)
+# endif
+#endif
+
#if !defined(__ARM_FEATURE_CRC32)
static uint32_t crc32_fast[4][256];
#endif
@@ -179,35 +196,35 @@
code = 0;
switch (l) {
- case 24577 ... 32768: code++; /* fall through */
- case 16385 ... 24576: code++; /* fall through */
- case 12289 ... 16384: code++; /* fall through */
- case 8193 ... 12288: code++; /* fall through */
- case 6145 ... 8192: code++; /* fall through */
- case 4097 ... 6144: code++; /* fall through */
- case 3073 ... 4096: code++; /* fall through */
- case 2049 ... 3072: code++; /* fall through */
- case 1537 ... 2048: code++; /* fall through */
- case 1025 ... 1536: code++; /* fall through */
- case 769 ... 1024: code++; /* fall through */
- case 513 ... 768: code++; /* fall through */
- case 385 ... 512: code++; /* fall through */
- case 257 ... 384: code++; /* fall through */
- case 193 ... 256: code++; /* fall through */
- case 129 ... 192: code++; /* fall through */
- case 97 ... 128: code++; /* fall through */
- case 65 ... 96: code++; /* fall through */
- case 49 ... 64: code++; /* fall through */
- case 33 ... 48: code++; /* fall through */
- case 25 ... 32: code++; /* fall through */
- case 17 ... 24: code++; /* fall through */
- case 13 ... 16: code++; /* fall through */
- case 9 ... 12: code++; /* fall through */
- case 7 ... 8: code++; /* fall through */
- case 5 ... 6: code++; /* fall through */
- case 4 : code++; /* fall through */
- case 3 : code++; /* fall through */
- case 2 : code++; /* fall through */
+ case 24577 ... 32768: code++; __fallthrough;
+ case 16385 ... 24576: code++; __fallthrough;
+ case 12289 ... 16384: code++; __fallthrough;
+ case 8193 ... 12288: code++; __fallthrough;
+ case 6145 ... 8192: code++; __fallthrough;
+ case 4097 ... 6144: code++; __fallthrough;
+ case 3073 ... 4096: code++; __fallthrough;
+ case 2049 ... 3072: code++; __fallthrough;
+ case 1537 ... 2048: code++; __fallthrough;
+ case 1025 ... 1536: code++; __fallthrough;
+ case 769 ... 1024: code++; __fallthrough;
+ case 513 ... 768: code++; __fallthrough;
+ case 385 ... 512: code++; __fallthrough;
+ case 257 ... 384: code++; __fallthrough;
+ case 193 ... 256: code++; __fallthrough;
+ case 129 ... 192: code++; __fallthrough;
+ case 97 ... 128: code++; __fallthrough;
+ case 65 ... 96: code++; __fallthrough;
+ case 49 ... 64: code++; __fallthrough;
+ case 33 ... 48: code++; __fallthrough;
+ case 25 ... 32: code++; __fallthrough;
+ case 17 ... 24: code++; __fallthrough;
+ case 13 ... 16: code++; __fallthrough;
+ case 9 ... 12: code++; __fallthrough;
+ case 7 ... 8: code++; __fallthrough;
+ case 5 ... 6: code++; __fallthrough;
+ case 4 : code++; __fallthrough;
+ case 3 : code++; __fallthrough;
+ case 2 : code++;
}
return code;