libssl is installed, then Open vSwitch will automatically build
with support for it.
- - Python 2.x, for x >= 4.
-
- - patch (The utility that is used to patch files).
+ - Python 2.7.
On Linux, you may choose to compile the kernel module that comes with
the Open vSwitch distribution or to use the kernel module built into
- Perl. Version 5.10.1 is known to work. Earlier versions should
also work.
- - Python 2.x, for x >= 4.
-
If you are going to extensively modify Open vSwitch, please consider
installing the following to obtain better warnings:
`% ./configure CC=clang`
+To supply special flags to the C compiler, specify them as CFLAGS on
+the configure command line. If you want the default CFLAGS, which
+include "-g" to build debug symbols and "-O2" to enable optimizations,
+you must include them yourself. For example, to build with the
+default CFLAGS plus "-mssse3", you might run configure as follows:
+
+ `% ./configure CFLAGS="-g -O2 -mssse3"`
+
+Note that these CFLAGS are not applied when building the Linux
+kernel module. Custom CFLAGS for the kernel module are supplied
+using the EXTRA_CFLAGS variable when running make. So, for example:
+
+ `% make EXTRA_CFLAGS="-Wno-error=date-time"
+
To build the Linux kernel module, so that you can run the
kernel-based switch, pass the location of the kernel build
directory on --with-linux. For example, to build for a running
For improved warnings if you installed "sparse" (see "Prerequisites"),
add C=1 to the command line.
+ Some versions of Clang and ccache are not completely compatible.
+ If you see unusual warnings when you use both together, consider
+ disabling ccache for use with Clang.
+
2. Consider running the testsuite. Refer to "Running the Testsuite"
below, for instructions.