Change Diagnostic Category size error from runtime to compiletime

[erichkeane]

Summary

Diagnostic Categories are fairly annoying, and are only enforced
by a runtime-debug-only assert. This puts in a touch more work
to get this all done at compile-time with static asserts.

[erichkeane]

Ugg... disregard the system-header-line-directive-ms-lineendings.c issue, I'm going to try to figure that out....

[rnk]

In D37122#851978, @erichkeane wrote:

Ugg... disregard the system-header-line-directive-ms-lineendings.c issue, I'm going to try to figure that out....

Yeah, I'm seeing issues with that as well. I'm not sure what's up.

[erichkeane]

In D37122#852018, @rnk wrote:

In D37122#851978, @erichkeane wrote:

Ugg... disregard the system-header-line-directive-ms-lineendings.c issue, I'm going to try to figure that out....

Yeah, I'm seeing issues with that as well. I'm not sure what's up.

I'm trying to research it... Some people (Stephen Hines & I) are having this issue with the git mirror, but others (CraigT) are not for some reason. There is a cfe-dev discussion started by Stephen, but I've really got no idea whats wrong.

[erichkeane]

Removed file due to git weirdness.

[rnk]

include/clang/Basic/AllDiagnostics.h

37 ↗

(On Diff #112651)

I'd prefer it if we sank this into a .cpp file so that when it fails, it doesn't create a waterfall of colorful static_assert errors. :)

[erichkeane]

Moved static assert into a .cpp file, DiagnosticIDs.cpp seems like the one that makes the most sense.

[rnk]

lgtm

cfe/trunk/include/clang/Basic/DiagnosticIDs.h

 #include <vector>
 
 namespace clang {
   class DiagnosticsEngine;
   class SourceLocation;
 
   // Import the diagnostic enums themselves.
   namespace diag {
+    // Size of each of the diagnostic categories.
+    enum {
+      DIAG_SIZE_COMMON        =  300,
+      DIAG_SIZE_DRIVER        =  200,
+      DIAG_SIZE_FRONTEND      =  100,
+      DIAG_SIZE_SERIALIZATION =  120,
+      DIAG_SIZE_LEX           =  400,
+      DIAG_SIZE_PARSE         =  500,
+      DIAG_SIZE_AST           =  110,
+      DIAG_SIZE_COMMENT       =  100,
+      DIAG_SIZE_SEMA          = 3500,
+      DIAG_SIZE_ANALYSIS      =  100
+    };
     // Start position for diagnostics.
     enum {
-      DIAG_START_COMMON        =                                 0,
-      DIAG_START_DRIVER        = DIAG_START_COMMON          +  300,
-      DIAG_START_FRONTEND      = DIAG_START_DRIVER          +  200,
-      DIAG_START_SERIALIZATION = DIAG_START_FRONTEND        +  100,
-      DIAG_START_LEX           = DIAG_START_SERIALIZATION   +  120,
-      DIAG_START_PARSE         = DIAG_START_LEX             +  400,
-      DIAG_START_AST           = DIAG_START_PARSE           +  500,
-      DIAG_START_COMMENT       = DIAG_START_AST             +  110,
-      DIAG_START_SEMA          = DIAG_START_COMMENT         +  100,
-      DIAG_START_ANALYSIS      = DIAG_START_SEMA            + 3500,
-      DIAG_UPPER_LIMIT         = DIAG_START_ANALYSIS        +  100
+      DIAG_START_COMMON        =                          0,
+      DIAG_START_DRIVER        = DIAG_START_COMMON        + DIAG_SIZE_COMMON,
+      DIAG_START_FRONTEND      = DIAG_START_DRIVER        + DIAG_SIZE_DRIVER,
+      DIAG_START_SERIALIZATION = DIAG_START_FRONTEND      + DIAG_SIZE_FRONTEND,
+      DIAG_START_LEX           = DIAG_START_SERIALIZATION + DIAG_SIZE_SERIALIZATION,
+      DIAG_START_PARSE         = DIAG_START_LEX           + DIAG_SIZE_LEX,
+      DIAG_START_AST           = DIAG_START_PARSE         + DIAG_SIZE_PARSE,
+      DIAG_START_COMMENT       = DIAG_START_AST           + DIAG_SIZE_AST,
+      DIAG_START_SEMA          = DIAG_START_COMMENT       + DIAG_SIZE_COMMENT,
+      DIAG_START_ANALYSIS      = DIAG_START_SEMA          + DIAG_SIZE_SEMA,
+      DIAG_UPPER_LIMIT         = DIAG_START_ANALYSIS      + DIAG_SIZE_ANALYSIS
     };
 
     class CustomDiagInfo;
 
     /// \brief All of the diagnostics that can be emitted by the frontend.
     typedef unsigned kind;
 
     // Get typedefs for common diagnostics.

cfe/trunk/lib/Basic/DiagnosticIDs.cpp

return Class == CLASS_REMARK ? diag::Flavor::Remark
                                  : diag::Flavor::WarningOrError;
   }
 
   bool operator<(const StaticDiagInfoRec &RHS) const {
     return DiagID < RHS.DiagID;
   }
 };
 
+#define STRINGIFY_NAME(NAME) #NAME
+#define VALIDATE_DIAG_SIZE(NAME)                                               \
+  static_assert(                                                               \
+      static_cast<unsigned>(diag::NUM_BUILTIN_##NAME##_DIAGNOSTICS) <          \
+          static_cast<unsigned>(diag::DIAG_START_##NAME) +                     \
+              static_cast<unsigned>(diag::DIAG_SIZE_##NAME),                   \
+      STRINGIFY_NAME(                                                          \
+          DIAG_SIZE_##NAME) " is insufficient to contain all "                 \
+                            "diagnostics, it may need to be made larger in "   \
+                            "DiagnosticIDs.h.");
+VALIDATE_DIAG_SIZE(COMMON)
+VALIDATE_DIAG_SIZE(DRIVER)
+VALIDATE_DIAG_SIZE(FRONTEND)
+VALIDATE_DIAG_SIZE(SERIALIZATION)
+VALIDATE_DIAG_SIZE(LEX)
+VALIDATE_DIAG_SIZE(PARSE)
+VALIDATE_DIAG_SIZE(AST)
+VALIDATE_DIAG_SIZE(COMMENT)
+VALIDATE_DIAG_SIZE(SEMA)
+VALIDATE_DIAG_SIZE(ANALYSIS)
+#undef VALIDATE_DIAG_SIZE
+#undef STRINGIFY_NAME
+
 } // namespace anonymous
 
 static const StaticDiagInfoRec StaticDiagInfo[] = {
 #define DIAG(ENUM, CLASS, DEFAULT_SEVERITY, DESC, GROUP, SFINAE, NOWERROR,     \
              SHOWINSYSHEADER, CATEGORY)                                        \
   {                                                                            \
     diag::ENUM, DEFAULT_SEVERITY, CLASS, DiagnosticIDs::SFINAE, NOWERROR,      \
         SHOWINSYSHEADER, CATEGORY, GROUP, STR_SIZE(DESC, uint16_t), DESC       \

 #undef DIAG
 };
 
 static const unsigned StaticDiagInfoSize = llvm::array_lengthof(StaticDiagInfo);
 
 /// GetDiagInfo - Return the StaticDiagInfoRec entry for the specified DiagID,
 /// or null if the ID is invalid.
 static const StaticDiagInfoRec *GetDiagInfo(unsigned DiagID) {
-  // If assertions are enabled, verify that the StaticDiagInfo array is sorted.
-#ifndef NDEBUG
-  static bool IsFirst = true; // So the check is only performed on first call.
-  if (IsFirst) {
-    assert(std::is_sorted(std::begin(StaticDiagInfo),
-                          std::end(StaticDiagInfo)) &&
-           "Diag ID conflict, the enums at the start of clang::diag (in "
-           "DiagnosticIDs.h) probably need to be increased");
-    IsFirst = false;
-  }
-#endif
-
   // Out of bounds diag. Can't be in the table.
   using namespace diag;
   if (DiagID >= DIAG_UPPER_LIMIT || DiagID <= DIAG_START_COMMON)
     return nullptr;
 
   // Compute the index of the requested diagnostic in the static table.
   // 1. Add the number of diagnostics in each category preceding the
   //    diagnostic and of the category the diagnostic is in. This gives us