[TableGen] Ignore fake args for parsing-related arg counts.

We should complain about the following:

```
void foo() __attribute__((unavailable("a", "b")));
```

Instead, we currently just ignore "b". (...We also end up ignoring "a",
because we assume elsewhere that this attribute can only have 1 or 0
args.)

This happens because `unavailable` has a fake enum arg, and
`AttributeList::{getMinArgs,getMaxArgs}` include fake args in their
counts.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@288388 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 0 deletions

diff --git a/utils/TableGen/ClangAttrEmitter.cpp b/utils/TableGen/ClangAttrEmitter.cpp
index 78a2eb118b..8185b6ab1e 100644
--- a/utils/TableGen/ClangAttrEmitter.cpp
+++ b/utils/TableGen/ClangAttrEmitter.cpp
@@ -2540,6 +2540,10 @@ static void emitArgInfo(const Record &R, std::stringstream &OS) {
   unsigned ArgCount = 0, OptCount = 0;
   bool HasVariadic = false;
   for (const auto *Arg : Args) {
+    // If the arg is fake, it's the user's job to supply it: general parsing
+    // logic shouldn't need to know anything about it.
+    if (Arg->getValueAsBit("Fake"))
+      continue;
     Arg->getValueAsBit("Optional") ? ++OptCount : ++ArgCount;
     if (!HasVariadic && isArgVariadic(*Arg, R.getName()))
       HasVariadic = true;