From fa707502501c3d2b5c0a172065077a50f9ec9bc0 Mon Sep 17 00:00:00 2001
From: Peter Wang <novalazy@gmail.com>
Date: Wed, 24 Jan 2018 17:37:23 +0300
Subject: [PATCH] Fix 'undeclared identifier USRSTACK' compiler error on
 OpenBSD-6.2 (back-port of commits ef879a9, 0bafc33 from 'master')

Issue #198 (bdwgc).

USRSTACK macro is defined in <machine/vmparam.h> but that is protected
by "ifdef _KERNEL" in <uvm/uvm_param.h>.

* include/private/gcconfig.h [POWERPC && OPENBSD && !GC_OPENBSD_THREADS]
(STACKBOTTOM): Add comment.
* include/private/gcconfig.h [(POWERPC || SPARC || I386 || MIPS
|| HP_PA || ALPHA || ARM32 || SH && !SH4 || X86_64) && OPENBSD
&& !GC_OPENBSD_THREADS] (STACKBOTTOM): Define only if USRSTACK is
defined.
* include/private/gcconfig.h [(POWERPC || SPARC || I386 || MIPS
|| HP_PA || ALPHA || ARM32 || SH && !SH4 || X86_64) && OPENBSD
&& !GC_OPENBSD_THREADS && !USRSTACK] (HEURISTIC2): Define.
* include/private/gcconfig.h [(MIPS || SH && !SH4) && OPENBSD]:
Reformat code.
---
 include/private/gcconfig.h | 96 ++++++++++++++++++++++++++------------
 1 file changed, 67 insertions(+), 29 deletions(-)

diff --git a/include/private/gcconfig.h b/include/private/gcconfig.h
index f77c9a86..ffbdc142 100644
--- a/include/private/gcconfig.h
+++ b/include/private/gcconfig.h
@@ -977,7 +977,13 @@
 #     ifndef GC_OPENBSD_THREADS
 #       include <sys/param.h>
 #       include <uvm/uvm_extern.h>
-#       define STACKBOTTOM ((ptr_t)USRSTACK)
+        /* USRSTACK is defined in <machine/vmparam.h> but that is       */
+        /* protected by _KERNEL in <uvm/uvm_param.h> file.              */
+#       ifdef USRSTACK
+#         define STACKBOTTOM ((ptr_t)USRSTACK)
+#       else
+#         define HEURISTIC2
+#       endif
 #     endif
       extern int __data_start[];
 #     define DATASTART ((ptr_t)__data_start)
@@ -1199,7 +1205,11 @@
 #     ifndef GC_OPENBSD_THREADS
 #       include <sys/param.h>
 #       include <uvm/uvm_extern.h>
-#       define STACKBOTTOM ((ptr_t)USRSTACK)
+#       ifdef USRSTACK
+#         define STACKBOTTOM ((ptr_t)USRSTACK)
+#       else
+#         define HEURISTIC2
+#       endif
 #     endif
       extern int __data_start[];
 #     define DATASTART ((ptr_t)__data_start)
@@ -1467,7 +1477,11 @@
 #       ifndef GC_OPENBSD_THREADS
 #         include <sys/param.h>
 #         include <uvm/uvm_extern.h>
-#         define STACKBOTTOM ((ptr_t)USRSTACK)
+#         ifdef USRSTACK
+#           define STACKBOTTOM ((ptr_t)USRSTACK)
+#         else
+#           define HEURISTIC2
+#         endif
 #       endif
         extern int __data_start[];
 #       define DATASTART ((ptr_t)__data_start)
@@ -1707,18 +1721,22 @@
 #     endif /* _ELF_ */
 #  endif
 #  ifdef OPENBSD
-#    define OS_TYPE "OPENBSD"
-#    define ALIGNMENT 4
+#     define OS_TYPE "OPENBSD"
+#     define ALIGNMENT 4
 #     ifndef GC_OPENBSD_THREADS
-#      include <sys/param.h>
-#      include <uvm/uvm_extern.h>
-#      define STACKBOTTOM ((ptr_t)USRSTACK)
-#    endif
-     extern int _fdata[];
-#    define DATASTART ((ptr_t)_fdata)
-     extern int _end[];
-#    define DATAEND ((ptr_t)(&_end))
-#    define DYNAMIC_LOADING
+#       include <sys/param.h>
+#       include <uvm/uvm_extern.h>
+#       ifdef USRSTACK
+#         define STACKBOTTOM ((ptr_t)USRSTACK)
+#       else
+#         define HEURISTIC2
+#       endif
+#     endif
+      extern int _fdata[];
+#     define DATASTART ((ptr_t)_fdata)
+      extern int _end[];
+#     define DATAEND ((ptr_t)(&_end))
+#     define DYNAMIC_LOADING
 #  endif
 #  ifdef FREEBSD
 #    define OS_TYPE "FREEBSD"
@@ -1840,7 +1858,11 @@
 #     ifndef GC_OPENBSD_THREADS
 #       include <sys/param.h>
 #       include <uvm/uvm_extern.h>
-#       define STACKBOTTOM ((ptr_t)USRSTACK)
+#       ifdef USRSTACK
+#         define STACKBOTTOM ((ptr_t)USRSTACK)
+#       else
+#         define HEURISTIC2
+#       endif
 #     endif
       extern int __data_start[];
 #     define DATASTART ((ptr_t)__data_start)
@@ -1870,7 +1892,11 @@
 #       ifndef GC_OPENBSD_THREADS
 #         include <sys/param.h>
 #         include <uvm/uvm_extern.h>
-#         define STACKBOTTOM ((ptr_t)USRSTACK)
+#         ifdef USRSTACK
+#           define STACKBOTTOM ((ptr_t)USRSTACK)
+#         else
+#           define HEURISTIC2
+#         endif
 #       endif
         extern int __data_start[];
 #       define DATASTART ((ptr_t)__data_start)
@@ -2272,7 +2298,11 @@
 #     ifndef GC_OPENBSD_THREADS
 #       include <sys/param.h>
 #       include <uvm/uvm_extern.h>
-#       define STACKBOTTOM ((ptr_t)USRSTACK)
+#       ifdef USRSTACK
+#         define STACKBOTTOM ((ptr_t)USRSTACK)
+#       else
+#         define HEURISTIC2
+#       endif
 #     endif
       extern int __data_start[];
 #     define DATASTART ((ptr_t)__data_start)
@@ -2325,17 +2355,21 @@
 #      define DYNAMIC_LOADING
 #   endif
 #   ifdef OPENBSD
-#      define OS_TYPE "OPENBSD"
-#      ifndef GC_OPENBSD_THREADS
-#        include <sys/param.h>
-#        include <uvm/uvm_extern.h>
-#        define STACKBOTTOM ((ptr_t)USRSTACK)
-#      endif
-       extern int __data_start[];
-#      define DATASTART ((ptr_t)__data_start)
-       extern int _end[];
-#      define DATAEND ((ptr_t)(&_end))
-#      define DYNAMIC_LOADING
+#     define OS_TYPE "OPENBSD"
+#     ifndef GC_OPENBSD_THREADS
+#       include <sys/param.h>
+#       include <uvm/uvm_extern.h>
+#       ifdef USRSTACK
+#         define STACKBOTTOM ((ptr_t)USRSTACK)
+#       else
+#         define HEURISTIC2
+#       endif
+#     endif
+      extern int __data_start[];
+#     define DATASTART ((ptr_t)__data_start)
+      extern int _end[];
+#     define DATAEND ((ptr_t)(&_end))
+#     define DYNAMIC_LOADING
 #   endif
 # endif
 
@@ -2393,7 +2427,11 @@
 #       ifndef GC_OPENBSD_THREADS
 #         include <sys/param.h>
 #         include <uvm/uvm_extern.h>
-#         define STACKBOTTOM ((ptr_t)USRSTACK)
+#         ifdef USRSTACK
+#           define STACKBOTTOM ((ptr_t)USRSTACK)
+#         else
+#           define HEURISTIC2
+#         endif
 #       endif
         extern int __data_start[];
         extern int _end[];
-- 
2.40.0