[PATCH] If the user requested a zero-base-shadow sanitizer, infer -pie and -fPIC when appropriate.

[Alexey Samsonov]

================
Comment at: lib/Driver/SanitizerArgs.h:68
@@ +67,3 @@
+  bool hasZeroBaseShadow() const {
+    return (Kind & HasZeroBaseShadow) || AsanZeroBaseShadow;
+  }
----------------
Can you just return (needsTsanRt() || needsMsanRt() || (needsAsanRt && AsanZeroBaseShadow) w/o introducing new SanitizeKind?

================
Comment at: lib/Driver/ToolChains.h:499
@@ -498,2 +498,3 @@
                                             ArgStringList &CC1Args) const;
+  virtual bool isPICDefault() const;
 
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Out of curiosity - why do you need this?

================
Comment at: lib/Driver/ToolChains.h:503
@@ -501,2 +502,3 @@
   std::vector<std::string> ExtraOpts;
+  bool HasZeroBaseShadow;
 
----------------
SanitizerHasZeroBaseShadow?

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Comment at: lib/Driver/Tools.cpp:5666
@@ +5665,3 @@
+  SanitizerArgs Sanitize(getToolChain(), Args);
+  const bool isPIE =
+    !Args.hasArg(options::OPT_shared) &&
----------------
s/isPIE/IsPIE


http://llvm-reviews.chandlerc.com/D502