From: Guillem Jover <guillem@debian.org>

Multiarch support.

The pmake system makefiles hardcode several standard library paths,
which will make other programs break due to those being located in
a different place on multiarch.

--- a/arch.c
+++ b/arch.c
@@ -165,15 +165,6 @@
 #include    "hash.h"
 #include    "dir.h"
 
-#ifdef TARGET_MACHINE
-#undef MAKE_MACHINE
-#define MAKE_MACHINE TARGET_MACHINE
-#endif
-#ifdef TARGET_MACHINE_ARCH
-#undef MAKE_MACHINE_ARCH
-#define MAKE_MACHINE_ARCH TARGET_MACHINE_ARCH
-#endif
-
 static Lst	  archives;   /* Lst of archives we've already examined */
 
 typedef struct Arch {
--- a/main.c
+++ b/main.c
@@ -151,6 +151,19 @@
 # define __arraycount(__x)	(sizeof(__x) / sizeof(__x[0]))
 #endif
 
+#ifdef TARGET_MACHINE
+#undef MAKE_MACHINE
+#define MAKE_MACHINE TARGET_MACHINE
+#endif
+#ifdef TARGET_MACHINE_ARCH
+#undef MAKE_MACHINE_ARCH
+#define MAKE_MACHINE_ARCH TARGET_MACHINE_ARCH
+#endif
+#ifdef TARGET_MACHINE_MULTIARCH
+#undef MAKE_MACHINE_MULTIARCH
+#define MAKE_MACHINE_MULTIARCH TARGET_MACHINE_MULTIARCH
+#endif
+
 Lst			create;		/* Targets to be made */
 time_t			now;		/* Time at start of make */
 GNode			*DEFAULT;	/* .DEFAULT node */
@@ -851,6 +864,7 @@
     	const char *machine = getenv("MACHINE");
 #endif
 	const char *machine_arch = getenv("MACHINE_ARCH");
+	const char *machine_multiarch = getenv("MACHINE_MULTIARCH");
 	char *syspath = getenv("MAKESYSPATH");
 	Lst sysMkPath;			/* Path of sys.mk */
 	char *cp = NULL, *start;
@@ -902,8 +916,8 @@
 	 * so we can share an executable for similar machines.
 	 * (i.e. m68k: amiga hp300, mac68k, sun3, ...)
 	 *
-	 * Note that both MACHINE and MACHINE_ARCH are decided at
-	 * run-time.
+	 * Note that all of MACHINE, MACHINE_ARCH and MACHINE_MULTIARCH
+	 * are decided at run-time.
 	 */
 	if (!machine) {
 #ifdef MAKE_NATIVE
@@ -946,6 +960,18 @@
 
 	myPid = getpid();		/* remember this for vFork() */
 
+	if (!machine_multiarch) {
+#ifndef MACHINE_MULTIARCH
+#ifdef MAKE_MACHINE_MULTIARCH
+	    machine_multiarch = MAKE_MACHINE_MULTIARCH;
+#else
+	    machine_multiarch = "unknown-unknown-unknown";
+#endif
+#else
+	    machine_multiarch = MACHINE_MULTIARCH;
+#endif
+	}
+
 	/*
 	 * Just in case MAKEOBJDIR wants us to do something tricky.
 	 */
@@ -954,6 +980,7 @@
 	Var_Set(".MAKE.OS", utsname.sysname, VAR_GLOBAL, 0);
 	Var_Set("MACHINE", machine, VAR_GLOBAL, 0);
 	Var_Set("MACHINE_ARCH", machine_arch, VAR_GLOBAL, 0);
+	Var_Set("MACHINE_MULTIARCH", machine_multiarch, VAR_GLOBAL, 0);
 #ifdef MAKE_VERSION
 	Var_Set("MAKE_VERSION", MAKE_VERSION, VAR_GLOBAL, 0);
 #endif
--- a/bmake.1
+++ b/bmake.1
@@ -2162,6 +2162,7 @@
 uses the following environment variables, if they exist:
 .Ev MACHINE ,
 .Ev MACHINE_ARCH ,
+.Ev MACHINE_MULTIARCH ,
 .Ev MAKE ,
 .Ev MAKEFLAGS ,
 .Ev MAKEOBJDIR ,
--- a/Makefile.boot
+++ b/Makefile.boot
@@ -4,7 +4,8 @@
 #
 # You only want to use this if you aren't running NetBSD.
 #
-# modify MACHINE and MACHINE_ARCH as appropriate for your target architecture
+# modify MACHINE, MACHINE_ARCH and MACHINE_MULTIARCH as appropriate for
+# your target architecture
 #
 CC=gcc -O -g
 
@@ -15,11 +16,13 @@
 
 MACHINE=i386
 MACHINE_ARCH=i386
+MACHINE_MULTIARCH=i386-linux-gnu
 # tested on HP-UX 10.20
 #MAKE_MACHINE=hp700
 #MAKE_MACHINE_ARCH=hppa
 CFLAGS= -DTARGET_MACHINE=\"${MACHINE}\" \
 	-DTARGET_MACHINE_ARCH=\"${MACHINE_ARCH}\" \
+	-DTARGET_MACHINE_MULTIARCH=\"${MACHINE_MULTIARCH}\" \
 	-DMAKE_MACHINE=\"${MACHINE}\"
 LIBS=