tools/clang/scripts/update.py

diff --git a/tools/clang/scripts/update.py b/tools/clang/scripts/update.py
index 0e2028e..4211e3077 100755
--- a/tools/clang/scripts/update.py
+++ b/tools/clang/scripts/update.py
@@ -26,7 +26,7 @@
 # Do NOT CHANGE this if you don't know what you're doing -- see
 # https://chromium.googlesource.com/chromium/src/+/master/docs/updating_clang.md
 # Reverting problematic clang rolls is safe, though.
-CLANG_REVISION = '263324'
+CLANG_REVISION = '264334'
 
 use_head_revision = 'LLVM_FORCE_HEAD_REVISION' in os.environ
 if use_head_revision:
@@ -437,13 +437,17 @@
         [cxx, '-print-file-name=libstdc++.so.6']).rstrip()
     os.environ['LD_LIBRARY_PATH'] = os.path.dirname(libstdcpp)
 
-  cflags = cxxflags = ldflags = []
+  cflags = []
+  cxxflags = []
+  ldflags = []
 
   base_cmake_args = ['-GNinja',
                      '-DCMAKE_BUILD_TYPE=Release',
                      '-DLLVM_ENABLE_ASSERTIONS=ON',
                      '-DLLVM_ENABLE_THREADS=OFF',
                      '-DLLVM_ENABLE_TIMESTAMPS=OFF',
+                     # Statically link MSVCRT to avoid DLL dependencies.
+                     '-DLLVM_USE_CRT_RELEASE=MT',
                      ]
 
   if args.bootstrap:
@@ -476,6 +480,10 @@
       # https://stackoverflow.com/questions/13050827
       cc = cc.replace('\\', '/')
       cxx = cxx.replace('\\', '/')
+      # If we're using VS 2015, tell the stage 1 compiler to act like it.
+      if GetVSVersion().ShortName().startswith('2015'):
+        cflags += ['-fms-compatibility-version=19']
+        cxxflags += ['-fms-compatibility-version=19']
     else:
       cc = os.path.join(LLVM_BOOTSTRAP_INSTALL_DIR, 'bin', 'clang')
       cxx = os.path.join(LLVM_BOOTSTRAP_INSTALL_DIR, 'bin', 'clang++')