[PATCH] D60233: [clang-scan-deps] initial outline of the tool that runs preprocessor to find dependencies over a JSON compilation database

[Alexandre Ganea via Phabricator via cfe-commits]

aganea added inline comments.


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Comment at: clang/test/ClangScanDeps/Inputs/regular_cdb.json:4
+  "directory": "DIR",
+  "command": "clang -c DIR/regular_cdb.cpp -IInputs -MD -MF DIR/regular_cdb.d",
+  "file": "DIR/regular_cdb.cpp"
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Is `-MD -MF` required for clang-scan-deps to work? Can't we append those arguments automatically, so that only include paths are needed in the CDB?

Would it possible for the tool to produce a collated file? A real-world usage would otherwise produce tens of thousands of files. Which then would be opened/parsed by the calling application.


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Comment at: clang/test/ClangScanDeps/regular_cdb.cpp:8
+// RUN: sed -e "s|DIR|%/t.dir|g" %S/Inputs/regular_cdb.json > %t.cdb
+// RUN: clang-scan-deps -compilation-database %t.cdb -j 1
+// RUN: cat %t.dir/regular_cdb.d | FileCheck %s
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Add a second test to excercice multi-threading? (by providing a few more files in the CDB)


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Comment at: clang/tools/clang-scan-deps/ClangScanDeps.cpp:140
+int main(int argc, const char **argv) {
+  llvm::cl::ResetAllOptionOccurrences();
+  llvm::cl::HideUnrelatedOptions(DependencyScannerCategory);
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`InitLLVM X(argc, argv);` is missing here to print callstacks in case of a crash, like the other tools.


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  https://reviews.llvm.org/D60233/new/

https://reviews.llvm.org/D60233