Fix an invalid check for duplicate option categories.

Summary:
The check performed in the comparator is invalid, as some STL
implementations enforce strict weak ordering by calling the comparator with the
same value. This check was also in a wrong place: the assertion would only fire
when -help was used. The new check is performed each time the category is
registered (we are not going to have thousands of them, so it's fine to do it in
O(N^2)).

Reviewers: jordan_rose

Reviewed By: jordan_rose

CC: cfe-commits, alexmc
Differential Revision: http://llvm-reviews.chandlerc.com/D2699

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200853 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Support/CommandLine.h b/include/llvm/Support/CommandLine.h
index 515b0bd00f93f657fad8a8d14188a0ae286913bd..b29fc8736034993d025625d5cb9f00ae73019eb6 100644 (file)
--- a/include/llvm/Support/CommandLine.h
+++ b/include/llvm/Support/CommandLine.h
@@ -149,8 +149,8 @@ private:
 public:
   OptionCategory(const char *const Name, const char *const Description = 0)
       : Name(Name), Description(Description) { registerCategory(); }
-  const char *getName() { return Name; }
-  const char *getDescription() { return Description; }
+  const char *getName() const { return Name; }
+  const char *getDescription() const { return Description; }
 };
 
 // The general Option Category (used as default category).

diff --git a/lib/Support/CommandLine.cpp b/lib/Support/CommandLine.cpp
index 16db4d639606515d052f1b5f7e942445c0d5d3a8..289bb87433f384e3c44faef518c179a6cbef20d5 100644 (file)
--- a/lib/Support/CommandLine.cpp
+++ b/lib/Support/CommandLine.cpp
@@ -125,8 +125,21 @@ static ManagedStatic<OptionCatSet> RegisteredOptionCategories;
 // Initialise the general option category.
 OptionCategory llvm::cl::GeneralCategory("General options");
 
+struct HasName {
+  HasName(StringRef Name) : Name(Name) {}
+  bool operator()(const OptionCategory *Category) const {
+    return Name == Category->getName();
+  }
+  StringRef Name;
+};
+
 void OptionCategory::registerCategory()
 {
+  assert(std::count_if(RegisteredOptionCategories->begin(),
+                       RegisteredOptionCategories->end(),
+                       HasName(getName())) == 0 &&
+         "Duplicate option categories");
+
   RegisteredOptionCategories->insert(this);
 }
 
@@ -1495,9 +1508,7 @@ public:
   // It shall return true if A's name should be lexographically
   // ordered before B's name. It returns false otherwise.
   static bool OptionCategoryCompare(OptionCategory *A, OptionCategory *B) {
-    int Length = strcmp(A->getName(), B->getName());
-    assert(Length != 0 && "Duplicate option categories");
-    return Length < 0;
+    return strcmp(A->getName(), B->getName()) < 0;
   }
 
   // Make sure we inherit our base class's operator=()