Accept -gdb option

mach/vax4/cg/mach.c

@@ -47,6 +47,21 @@ con_mult(sz)
 	fprintf(codefile,".data4\t%s\n",str);
 }
 
+#ifdef MACH_OPTIONS
+static int gdb_flag = 0;
+
+mach_option(s)
+	char *s;
+{
+	if (! strcmp(s, "-gdb")) {
+		gdb_flag = 1;
+	}
+	else {
+		error("Unknown flag %s", s);
+	}
+}
+#endif /* MACH_OPTIONS */
+
 mes(mesno)
 	word	mesno;
 {
@@ -77,9 +92,14 @@ mes(mesno)
 		argt = getarg(cst_ptyp);
 		a2 = argval;
 		argt = getarg(cst_ptyp|nof_ptyp|sof_ptyp|ilb_ptyp|pro_ptyp);
-#ifdef DBX
-		if (a1 == N_PSYM) {
-			argval += 4;
+#ifdef MACH_OPTIONS
+		if (gdb_flag) {
+			if (a1 == N_PSYM) {
+				/* Change offset from AB into offset from
+				   the frame pointer (ab).
+				*/
+				argval += 4;
+			}
 		}
 #endif
 		fprintf(codefile, "%s, 0x%x, %d\n", strarg(argt), a1, a2);
@@ -93,12 +113,14 @@ mes(mesno)
 			argt = getarg(cst_ptyp);
 		}
 		swtxt();
-#ifndef DBX
-		if (argval == N_SLINE) {
+		if (argval == N_SLINE
+#ifdef MACH_OPTIONS
+		    && ! gdb_flag
+#endif
+		) {
 			fputs("calls $0,___u_LiB\n", codefile);
 			cleanregs();	/* debugger might change variables */
 		}
-#endif
 		fprintf(codefile, ".symd \"%s\", 0x%x,", str, (int) argval);
 		argt = getarg(cst_ptyp);
 		fprintf(codefile, "%d\n", (int) argval);

mach/vax4/cg/mach.h

@@ -27,5 +27,6 @@
 #define con_dlb(x)	fprintf(codefile,".data4\t%s\n",x)
 
 #define BSS_INIT	0
+#define MACH_OPTIONS
 
 #define modhead		".sect .text\n.sect .rom\n.sect .data\n.sect .bss\n"