[docs] Prevent O0 optnone for opt input

If we just compile with -O0, clang will add optnone attributes
everywhere, so opt won't actually be able to perform any passes.
Instruct clang to not emit the optnone so opt can do its thing.

Differential Revision: https://reviews.llvm.org/D56950

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352550 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/HowToSubmitABug.rst b/docs/HowToSubmitABug.rst
index 7881a6e8dcc30fbb6571e6ef6ae425f1b090e835..d276ee8681f380121672c153fca703edc9d2437c 100644 (file)
--- a/docs/HowToSubmitABug.rst
+++ b/docs/HowToSubmitABug.rst
@@ -84,8 +84,8 @@ Compile-time optimization bugs
 ------------------------------
 
 If you find that a bug crashes in the optimizer, compile your test-case to a
-``.bc`` file by passing "``-emit-llvm -O0 -c -o foo.bc``".
-Then run:
+``.bc`` file by passing "``-emit-llvm -O1 -Xclang -disable-llvm-passes -c -o
+foo.bc``".  Then run:
 
 .. code-block:: bash