Add comment about the importance of being adjacent. NFC

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@240328 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index 987e063039ca60870de2ebc1def2c204c6d146d2..e1571937482463ddc9830a36e3148659d60484a2 100644 (file)
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -2896,6 +2896,9 @@ Tool *Solaris::buildLinker() const {
 /// Distribution (very bare-bones at the moment).
 
 enum Distro {
+  // NB: Releases of a particular Linux distro should be kept together
+  // in this enum, because some tests are done by integer comparison against
+  // the first and last known member in the family, e.g. IsRedHat().
   ArchLinux,
   DebianLenny,
   DebianSqueeze,