[docs] Add a note to docs/README.txt

Added note to docs/README.txt on how to check the reachibility of
external links in the documentation.

Patch by Dan Liew!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206924 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/README.txt b/docs/README.txt
index 22cf93077959d82380a89ea3d1879e6367de47db..3d634292980832537c98cae7115b038c2ccd1de2 100644 (file)
--- a/docs/README.txt
+++ b/docs/README.txt
@@ -40,3 +40,12 @@ The correspondence between .rst files and man pages is
 These .rst files are also included during HTML generation so they are also
 viewable online (as noted above) at e.g.
 `http://llvm.org/docs/CommandGuide/Foo.html`.
+
+Checking links
+==============
+
+The reachibility of external links in the documentation can be checked by
+running:
+
+    cd docs/
+    make -f Makefile.sphinx linkcheck