llvm-build: Add sketchy support for preserving comments when using
--write-llvmbuild.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146434 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/CommandGuide/llvm-build.pod b/docs/CommandGuide/llvm-build.pod
index 78648ba..14e08cb 100644
--- a/docs/CommandGuide/llvm-build.pod
+++ b/docs/CommandGuide/llvm-build.pod
@@ -46,7 +46,10 @@
=item B<--write-llvmbuild>
Write out new I<LLVMBuild.txt> files based on the loaded components. This is
-useful for auto-upgrading the schema of the files.
+useful for auto-upgrading the schema of the files. B<llvm-build> will try to a
+limited extent to preserve the comments which were written in the original
+source file, although at this time it only preserves block comments that preceed
+the section names in the I<LLVMBuild> files.
=item B<--write-cmake-fragment>