[PULL 1/7] linux-user: limit check to HOST_LONG_BITS < TARGET_ABI_BITS

[Thomas Huth]

From: Alex Bennée <alex.bennee@linaro.org>

Newer clangs rightly spot that you can never exceed the full address
space of 64 bit hosts with:

  linux-user/elfload.c:2076:41: error: result of comparison 'unsigned
  long' > 18446744073709551615 is always false
  [-Werror,-Wtautological-type-limit-compare]
  4685         if ((guest_hiaddr - guest_base) > ~(uintptr_t)0) {
  4686             ~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~
  4687 1 error generated.

So lets limit the check to 32 bit hosts only.

Fixes: ee94743034bf
Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200525131823.715-8-thuth@redhat.com>
[thuth: Use HOST_LONG_BITS < TARGET_ABI_BITS instead of HOST_LONG_BITS == 32]
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 linux-user/elfload.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 01a9323a63..ebc663ea0b 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -2073,12 +2073,14 @@ static void pgb_have_guest_base(const char *image_name, 
abi_ulong guest_loaddr,
             exit(EXIT_FAILURE);
         }
     } else {
+#if HOST_LONG_BITS < TARGET_ABI_BITS
         if ((guest_hiaddr - guest_base) > ~(uintptr_t)0) {
             error_report("%s: requires more virtual address space "
                          "than the host can provide (0x%" PRIx64 ")",
                          image_name, (uint64_t)guest_hiaddr - guest_base);
             exit(EXIT_FAILURE);
         }
+#endif
     }
 
     /*
-- 
2.18.1