Extend configure.sample and the relevant spec part

[exim.git] / src / OS / os.h-Linux

diff --git a/src/OS/os.h-Linux b/src/OS/os.h-Linux
index 5186ec89dde44f645efa85bf55ae03954ed24b8a..05c153e2c1aa68aacb800b7de2db60195f37453a 100644 (file)
--- a/src/OS/os.h-Linux
+++ b/src/OS/os.h-Linux
@@ -1,8 +1,8 @@
 /* Exim: OS-specific C header file for Linux */
 
-/* Some weird variants may require invocation with C99 and features.h
-inclusion to build, with the 64-bit arithmetic. Make compiler selection
-their problem, but build anyway. */
+/* Some old systems we've received bug-reports for have a <limits.h> which
+does not pull in <features.h>.  Best to just pull it in now and have done
+with the issue. */
 
 #include <features.h>
 
@@ -44,9 +44,6 @@ storage" as quickly as Exim thinks they are. */
 
 #define NEED_SYNC_DIRECTORY
 
-/* Other OS have "const" in here */
-#define ICONV_ARG2_TYPE char **
-
 #define os_find_running_interfaces os_find_running_interfaces_linux
 
 /* Need a prototype for the Linux-specific function. The structure hasn't
@@ -57,4 +54,16 @@ extern struct ip_address_item *os_find_running_interfaces_linux(void);
 
 #endif /* __linux__ */
 
+/* Some folks running "unusual" setups with very old libc environments have
+found that _GNU_SOURCE=1 before <features.h> is not sufficient to define some
+constants needed for 64-bit arithmetic.  If you encounter build errors based
+on LLONG_MIN being undefined and various other escape hatches have not helped,
+then change the 0 to 1 in the next block. */
+
+#if 0
+# define LLONG_MIN LONG_LONG_MIN
+# define LLONG_MAX LONG_LONG_MAX
+#endif
+
+
 /* End */