Really mean it about strict C99 compliance.

Makefile

@@ -1,5 +1,6 @@
 # Makefile for the open-source release of adventure 2.5
 
+CCFLAGS=-std=c99
 LIBS=-lrt
 UNAME_S := $(shell uname -s)
 GCCVERSIONGTEQ4 := $(shell expr `gcc -dumpversion | cut -f1 -d.` \>= 4)
@@ -13,10 +14,10 @@ OBJS=main.o init.o actions1.o actions2.o score.o misc.o
 SOURCES=$(OBJS:.o=.c) COPYING NEWS README TODO adventure.text advent.text control misc.h main.h share.h funcs.h
 
 .c.o:
-	$(CC) -O $(DBX) -c $<
+	$(CC) $(CCFLAGS) -O $(DBX) -c $<
 
 advent:	$(OBJS) database.o
-	$(CC) -Wall -std=c99 -O $(DBX) -o advent $(OBJS) database.o $(LIBS)
+	$(CC) $(CCFLAGS) -O $(DBX) -o advent $(OBJS) database.o $(LIBS)
 
 main.o:		main.h misc.h funcs.h database.h
 
@@ -32,7 +33,7 @@ misc.o:		misc.h main.h database.h
 
 database.c database.h: compile
 	./compile
-	$(CC) $(OPTIONS) -O $(DBX) -c database.c
+	$(CC) $(CCFLAGS) -O $(DBX) -c database.c
 
 clean:
 	rm -f *.o advent advent.html advent.6 database.[ch] compile

actions1.c

@@ -523,7 +523,7 @@ L8300:	SPK=201;
 /*  This next part is shared with the "resume" code.  The two cases are
  *  distinguished by the value of kk (-1 for suspend, +1 for resume). */
 
-L8305:	DATIME(I,K);
+L8305:	DATIME(&I,&K);
 	K=I+650*K;
 	SAVWRD(KK,K);
 	K=VRSION;

main.c

@@ -8,6 +8,7 @@
 #include <stdbool.h>
 #include <getopt.h>
 #include <signal.h>
+#include <time.h>
 #include "main.h"
 #include "database.h"
 #include "misc.h"
@@ -920,4 +921,5 @@ L12400: LIMIT= -1;
 L18999: RSPEAK(SPK);
 L19000: RSPEAK(136);
 	score(0);
+	return true;
 }

misc.c

@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <sys/time.h>
 #include "main.h"
 #include "share.h"	/* for SETUP */
 #include "misc.h"
@@ -1002,5 +1003,11 @@ L30:	if(IN)IGNORE(fread(ARR,sizeof(long),250,F));
 
 
 
+void DATIME(long* D, long* T) {
+  struct timeval tv;
+  gettimeofday(&tv, NULL);
+  *D = (long) tv.tv_sec;
+  *T = (long) tv.tv_usec;
+}
 long fIABS(N)long N; {return(N<0? -N : N);}
 long fMOD(N,M)long N, M; {return(N%M);}

misc.h

@@ -1,4 +1,3 @@
-#include <time.h>
 #include <stdio.h>
 #include <stdbool.h>
 
@@ -68,7 +67,7 @@ extern void fMPINIT();
 #define MPINIT() fMPINIT()
 extern void fSAVEIO(long,long,long*);
 #define SAVEIO(OP,IN,ARR) fSAVEIO(OP,IN,ARR)
-#define DATIME(D,T) do {struct timespec ts; clock_gettime(CLOCK_REALTIME, &ts); D=ts.tv_sec, T=ts.tv_nsec;} while (0)
+extern void DATIME(long*, long*);
 extern long fIABS(long);
 #define IABS(N) fIABS(N)
 extern long fMOD(long,long);