[PATCH] D18088: Add a new warning to notify users of mismatched SDK and deployment target

[Richard Smith via cfe-commits]

rsmith added a subscriber: rsmith.

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Comment at: lib/Driver/ToolChains.cpp:718-720
@@ +717,5 @@
+    StringRef isysroot = A->getValue();
+    // Assume SDK has path: SOME_PATH/SDKs/PlatformXX.YY.sdk
+    size_t BeginSDK = isysroot.rfind("SDKs/");
+    size_t EndSDK = isysroot.rfind(".sdk");
+    if (BeginSDK != StringRef::npos && EndSDK != StringRef::npos) {
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This seems to get a couple of corner cases wrong (`/` between the platform name and `.sdk`, `.sdk` not at the end of the path component, ...). Have you considered using `llvm::sys::path`'s path iterators here? Not a big deal either way, though.

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Comment at: lib/Driver/ToolChains.cpp:722
@@ +721,3 @@
+    if (BeginSDK != StringRef::npos && EndSDK != StringRef::npos) {
+      StringRef SDK = isysroot.slice(BeginSDK + 5, EndSDK);
+      if (!SDK.startswith(getPlatformFamily()))
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According to `slice`'s documentation, if `EndSDK < BeginSDK + 5`, this `slice` call will return a slice from `BeginSDK + 5` to the end of the string, and you won't be checking for a `.sdk` prefix as you intended to.


http://reviews.llvm.org/D18088