Re: [Libunwind-devel] Multi-platform unwinding i386 binary on x86_64

[Nurdin Premji]

Nurdin Premji wrote:
> Can this be committed?
This forces the memory mapped in from the inferior process to be mapped 
only into the first 32 bits of memory. This avoids the situation of 
truncated memory addresses when unwinding a 32 bit process on a 64  bit 
host.
--- libunwind-0.99-alpha/src/elfxx.h    2006-07-26 23:13:14.000000000 -0400
+++ mainworkspace/frysk/frysk-imports/libunwind/src/elfxx.h     2007-04-24 
16:42:55.000000000 -0400
@@ -1,6 +1,7 @@
 /* libunwind - a platform-independent unwind library
    Copyright (C) 2003, 2005 Hewlett-Packard Co
        Contributed by David Mosberger-Tang <address@hidden>
+   Copyright Red Hat 2007
 
 This file is part of libunwind.
 
@@ -42,6 +43,10 @@
 # define elf_w(x)      _Uelf64_##x
 #endif
 
+#ifndef MAP_32BIT
+# define MAP_32BIT 0
+#endif
+
 static inline int
 elf_map_image (struct elf_image *ei, const char *path)
 {
@@ -59,7 +64,7 @@
     }
 
   ei->size = stat.st_size;
-  ei->image = mmap (NULL, ei->size, PROT_READ, MAP_PRIVATE, fd, 0);
+  ei->image = mmap (NULL, ei->size, PROT_READ, MAP_PRIVATE | MAP_32BIT, fd, 0);
   close (fd);
   if (ei->image == MAP_FAILED)
     return -1;