[m-rev.] for review: Warning about issues with 64-bit Windows and low-level C grades.

[Peter Wang]

Julien, do you remember if you were able to bootcheck the Win64 port?

---

Warning about issues with 64-bit Windows and low-level C grades.

README.MinGW:
README.MinGW-cross:
	As above.

diff --git a/README.MinGW b/README.MinGW
index 6c4e39d..a8d4a77 100644
--- a/README.MinGW
+++ b/README.MinGW
@@ -2,6 +2,10 @@ This file documents the port of Mercury to Windows using the either the MinGW
 or MinGW64 ports of GCC, i.e. the i686-pc-mingw32 or x86_64-w64-mingw32
 configurations.
 
+NOTE: There are problems with 64-bit executables in some low-level C grades,
+namely 'asm_fast*' and 'asm_jump*' grades. The 'none*' and 'reg*' grades
+do appear to work correctly in our limited testing.
+
 -----------------------------------------------------------------------------
 
 BUILDING WITH MINGW
diff --git a/README.MinGW-cross b/README.MinGW-cross
index 010fe3d..3334f69 100644
--- a/README.MinGW-cross
+++ b/README.MinGW-cross
@@ -7,6 +7,10 @@ After copying and adjusting some paths, the Mercury installation should be
 usable on Windows.  When combined with a native Mercury compiler, it can be
 used to cross-compile Mercury applications for Windows.
 
+NOTE: There are problems with 64-bit executables in some low-level C grades,
+namely 'asm_fast*' and 'asm_jump*' grades. The 'none*' and 'reg*' grades
+do appear to work correctly in our limited testing.
+
 -----------------------------------------------------------------------------
 
 PREREQUISITES