/* For AIX, it turns out compiling emacs under AIX 3.2.4 REQUIRES "cc -g"
because "cc -O" crashes. Under AIX 3.2.5, "cc -O" is required because
"cc -g" crashes. Go figure. --floppy@merlin.mit.edu */
-#ifndef __GNUC__
+/* The above isn't generally true. If it occurs with some compiler
+ release, seek a fixed version, be it XLC or GCC. The XLC version
+ isn't tied to the OS version on AIX any more than elsewhere. XLC
+ (the IBM compiler) can use -g with -O. (-O3 is also a possibility
+ for the optimization level.) -- fx, after David Edelsohn. */
#undef C_DEBUG_SWITCH
-#undef C_OPTIMIZE_SWITCH
-#define C_DEBUG_SWITCH -O
-#define C_OPTIMIZE_SWITCH -O
-#endif
+#define C_DEBUG_SWITCH -g -O
+
+/* Perry Smith <pedz@ddivt1.austin.ibm.com> says these are correct. */
+#define SIGNALS_VIA_CHARACTERS
+#define MAIL_USE_LOCKF
+#define CLASH_DETECTION
+
+/* Perry Smith <pedz@ddivt1.austin.ibm.com> says these are correct. */
+#define POSIX_SIGNALS
+#undef sigmask
+#undef sigsetmask
+#undef _setjmp
+#undef _longjmp
+
+/* Bill Woodward <wpwood@austin.ibm.com> says:
+ libIM *must* precede libXm, to avoid getting aixLoadIM error messages. */
+#define LIB_MOTIF -lIM -lXm
+
+/* arch-tag: 692b3acb-5383-4cfb-93f6-378b5c48c75e
+ (do not change this comment) */