Miscellaneous fixes for big-endian systems

This patch fixes a bunch of issues that show up on big-endian systems:

- The gnu_libstdcpp.py script doesn't follow the way libstdc++ encodes
  bit vectors: it should identify the enclosing *word* and then access
  the appropriate bit within that word.  Instead, the script simply
  operates on bytes.  This gives the same result on little-endian
  systems, but not on big-endian.

- lldb_private::formatters::WCharSummaryProvider always assumes wchar_t
  is UTF16, even though it could also be UTF8 or UTF32.  This is mostly
  not an issue on little-endian systems, but immediately fails on BE.
  Fixed by checking the size of wchar_t like WCharStringSummaryProvider
  already does.

- ClangASTContext::GetChildCompilerTypeAtIndex uses uint32_t to access
  the virtual base offset stored in the vtable, even though the size
  of this field matches the target pointer size according to the C++
  ABI.  Again, this is mostly not visible on LE, but fails on BE.

- Process::ReadStringFromMemory uses strncmp to search for a terminator
  consisting of multiple zero bytes.  This doesn't work since strncmp
  will stop already at the first zero byte.  Use memcmp instead.

Differential Revision: http://reviews.llvm.org/D18983

llvm-svn: 266313

1 files changed, 1 insertions, 1 deletions

diff --git a/lldb/source/Target/Process.cpp b/lldb/source/Target/Process.cpp
index 34557e04936..6a9328fc9bc 100644
--- a/lldb/source/Target/Process.cpp
+++ b/lldb/source/Target/Process.cpp
@@ -2437,7 +2437,7 @@ Process::ReadStringFromMemory (addr_t addr, char *dst, size_t max_bytes, Error &
             // Search for a null terminator of correct size and alignment in bytes_read
             size_t aligned_start = total_bytes_read - total_bytes_read % type_width;
             for (size_t i = aligned_start; i + type_width <= total_bytes_read + bytes_read; i += type_width)
-                if (::strncmp(&dst[i], terminator, type_width) == 0)
+                if (::memcmp(&dst[i], terminator, type_width) == 0)
                 {
                     error.Clear();
                     return i;