[PATCH] D102669: [analyzer][ctu] Fix wrong 'multiple definitions' errors caused by space characters in lookup names when parsing the ctu index file

[Ella Ma via Phabricator via cfe-commits]

OikawaKirie created this revision.
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This error was found when analyzing MySQL with CTU enabled.

When there are space characters in the lookup name, the current delimiter searching strategy will make the file path wrongly parsed.
And when two lookup names have the same prefix before their first space characters, a 'multiple definitions' error will be wrongly reported.

e.g. The lookup names for the two lambda exprs in the test case are `c:@S at G@F at G#@Sa at F@operator int (*)(char)#1` and `c:@S at G@F at G#@Sa at F@operator bool (*)(char)#1` respectively. And their prefixes are both `c:@S at G@F at G#@Sa at F@operator` when using the first space character as the delimiter.

This patch solves the problem by replacing `find` with `rfind` for the delimiter, as the chance of file paths having space characters seems to be far less than the lookup name.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D102669

Files:
  clang/lib/CrossTU/CrossTranslationUnit.cpp
  clang/test/Analysis/Inputs/ctu-lookup-name-with-space.cpp
  clang/test/Analysis/ctu-lookup-name-with-space.cpp


Index: clang/test/Analysis/ctu-lookup-name-with-space.cpp
===================================================================
--- /dev/null
+++ clang/test/Analysis/ctu-lookup-name-with-space.cpp
@@ -0,0 +1,29 @@
+// RUN: rm -rf %t
+// RUN: mkdir %t
+
+// RUN: cp %s %t/trigger.cpp
+// RUN: cp %S/Inputs/ctu-lookup-name-with-space.cpp %t/importee.cpp
+// RUN: echo '"%t/importee.cpp" : ["g++", "-c", "%t/importee.cpp"]' > %t/invocations.yaml
+// RUN: echo '[{"directory": "%t", "command": "g++ -c %t/importee.cpp", "file": "%t/importee.cpp"}, {"directory": "%t", "command": "g++ -c %t/trigger.cpp", "file": "%t/trigger.cpp"}]' > %t/compile_commands.json
+
+// RUN: %clang_extdef_map -p %t %t/importee.cpp > %t/externalDefMap.txt
+
+// RUN: cd %t && %clang_cc1 -fsyntax-only -analyze \
+// RUN:   -analyzer-checker=core \
+// RUN:   -analyzer-config experimental-enable-naive-ctu-analysis=true \
+// RUN:   -analyzer-config ctu-dir=. \
+// RUN:   -analyzer-config ctu-invocation-list=invocations.yaml \
+// RUN:   trigger.cpp 2>&1 | FileCheck importee.cpp
+
+// RUN: cd %t && %clang_cc1 -fsyntax-only -analyze \
+// RUN:   -analyzer-checker=core \
+// RUN:   -analyzer-config experimental-enable-naive-ctu-analysis=true \
+// RUN:   -analyzer-config ctu-dir=. \
+// RUN:   -analyzer-config ctu-invocation-list=invocations.yaml \
+// RUN:   -verify trigger.cpp
+
+int importee(int);
+
+void trigger() {
+  importee(0); // expected-warning at importee.cpp:13 {{Division by zero}}
+}
Index: clang/test/Analysis/Inputs/ctu-lookup-name-with-space.cpp
===================================================================
--- /dev/null
+++ clang/test/Analysis/Inputs/ctu-lookup-name-with-space.cpp
@@ -0,0 +1,14 @@
+void f(int (*)(char));
+void f(bool (*)(char));
+
+struct G {
+  G() {
+    // CHECK-NOT: error: multiple definitions are found for the same key in index
+    f([](char) -> int { return 42; });
+    f([](char) -> bool { return true; });
+  }
+};
+
+int importee(int X) {
+  return 1 / X;
+}
Index: clang/lib/CrossTU/CrossTranslationUnit.cpp
===================================================================
--- clang/lib/CrossTU/CrossTranslationUnit.cpp
+++ clang/lib/CrossTU/CrossTranslationUnit.cpp
@@ -157,7 +157,7 @@
   unsigned LineNo = 1;
   while (std::getline(ExternalMapFile, Line)) {
     StringRef LineRef{Line};
-    const size_t Delimiter = LineRef.find(' ');
+    const size_t Delimiter = LineRef.rfind(' ');
     if (Delimiter > 0 && Delimiter != std::string::npos) {
       StringRef LookupName = LineRef.substr(0, Delimiter);
 


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