[PATCH] New options for asan-symbolizer script: set cross-compile prefix, set path to sysroot, print help message

[Alexander Potapenko]

LGTM with nits (please fix them and re-upload before landing)

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Comment at: lib/asan/scripts/asan_symbolize.py:18
@@ -17,2 +17,3 @@
 import termios
+import argparse
 
----------------
Please keep the import list sorted alphabetically.

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Comment at: lib/asan/scripts/asan_symbolize.py:417
@@ +416,3 @@
+  -s path_to_sysroot            Path to sysroot for sanitized binaries
+  -d, --demangle                Demangle function names
+Example:
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Please fix the usage to reflect the newly added options.

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Comment at: lib/asan/scripts/asan_symbolize.py:433
@@ +432,3 @@
+    help='set path to sysroot for sanitized binaries')
+  parser.add_argument('-p', metavar='PREFIX',
+    help='set prefix for binutils')
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-b and "BINUTILS_PREFIX", maybe? (unless PREFIX is some standard name used by the toolchain)

http://reviews.llvm.org/D4703