Document the -Ov option, minor fix for gcc -Og

The -Ov option is useful but was undocumented.

Add an initialization to keep gcc from complaining at optimization
level -Og.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/doc/nasmdoc.src b/doc/nasmdoc.src
index bdec6b6e..ea6f10f2 100644
--- a/doc/nasmdoc.src
+++ b/doc/nasmdoc.src
@@ -746,7 +746,9 @@ with a \i{stub preprocessor} which does nothing.
 \S{opt-O} The \i\c{-O} Option: Specifying \i{Multipass Optimization}
 
 Using the \c{-O} option, you can tell NASM to carry out different
-levels of optimization.  The syntax is:
+levels of optimization. Multiple flags can be specified after the
+\c{-O} options, some of which can be combined in a single option,
+e.g. \c{-Oxv}.
 
 \b \c{-O0}: No optimization. All operands take their long forms,
         if a short form is not specified, except conditional jumps.
@@ -764,6 +766,9 @@ levels of optimization.  The syntax is:
         releases, the letter \c{x} may also be any number greater than
         one. This number has no effect on the actual number of passes.
 
+\b \c{-Ov}: At the end of assembly, print the number of passes
+        actually executed.
+
 The \c{-Ox} mode is recommended for most uses, and is the default
 since NASM 2.09.