[PATCH] D11958: Add a -gmodules option to the clang driver.

[Richard Smith via cfe-commits]

rsmith added a subscriber: rsmith.

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Comment at: include/clang/Frontend/CodeGenOptions.def:164-165
@@ -163,1 +163,4 @@
 
+CODEGENOPT(DebugTypeExtRefs, 1, 0) ///< Whether or not debug info should contain
+                                   ///< external references to a PCH or module.
+
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Does this flag end up in the module hash? It presumably should do so.

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Comment at: lib/Driver/Tools.cpp:3708
@@ +3707,3 @@
+    CmdArgs.push_back("-dwarf-ext-refs");
+    CmdArgs.push_back("-fmodule-format=obj");
+  }
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What happens if we get a module cache hash collision between module files with different formats? This didn't really matter when the choice was essentially made per-platform, but if it's affected by a user-facing -g flag, we should make sure this works reliably. (You can probably test this by using `-disable-module-hash` and then using the same module with two different module formats specified.)


Repository:
  rL LLVM

http://reviews.llvm.org/D11958