Hi Stephane,
When compiling the code of virtuoso-opensource code 5.0.11 with the GCC flags for detecting format string vulnerabilities, some of them show up. For your consideration, here is a patch that removes the corresponding warnings or errorsraised.
As discussed off-list, this patch is not usable in it's current form, but we will fix the warning messages raised by your gcc flags in the next version of VOS.
Patrick
