Don't test for __attribute__ in the configure script.

Instead, use compiler test macros for the one remaining case where we
tested for __attribute__ to check whether that *particular* attribute is
supported.

1 files changed, 8 insertions, 6 deletions

diff --git a/extract.h b/extract.h
index 8a8b6024..aa3ff991 100644
--- a/extract.h
+++ b/extract.h
@@ -24,6 +24,7 @@
 #endif
 
 #include <pcap/pcap-inttypes.h>
+#include <pcap/compiler-tests.h>
 
 /*
  * Macros to extract possibly-unaligned big-endian integral values.
@@ -32,15 +33,16 @@
 /*
  * The processor doesn't natively handle unaligned loads.
  */
-#if defined(__GNUC__) && defined(HAVE___ATTRIBUTE__) && \
+#if PCAP_IS_AT_LEAST_GNUC_VERSION(2,0) && \
     (defined(__alpha) || defined(__alpha__) || \
      defined(__mips) || defined(__mips__))
-
 /*
- * This is a GCC-compatible compiler and we have __attribute__, which
- * we assume that mean we have __attribute__((packed)), and this is
- * MIPS or Alpha, which has instructions that can help when doing
- * unaligned loads.
+ * This is MIPS or Alpha, which don't natively handle unaligned loads,
+ * but which have instructions that can help when doing unaligned
+ * loads, and this is GCC 2.0 or later or a compiler that claims to
+ * be GCC 2.0 or later, which we assume that mean we have
+ * __attribute__((packed)), which we can use to convince the compiler
+ * to generate those instructions.
  *
  * Declare packed structures containing a uint16_t and a uint32_t,
  * cast the pointer to point to one of those, and fetch through it;