20/12/2018 11:53, Mattias Rönnblom: > On 2018-12-19 22:45, Thomas Monjalon wrote: > > 14/12/2018 21:28, Mattias Rönnblom: > >> On 2018-12-14 20:07, Jeff Shaw wrote: > >>>>> The code prior to this commit produced the following warning when > >>>>> compiled with "-Wvla -std=c90". > >>>>> > >>>>> warning: ISO C90 forbids variable length array ‘array’ [-Wvla] > >>>>> > >>>>> This commit removes the variable length array from the PMD debug > >>>>> trace function by allocating memory dynamically on the stack using > >>>>> alloca(). > >>>> > >>>> Is alloca() even included in *any* C standard? As far as I see, it just > >>>> achieves the same thing in an uglier, less portable way than VLAs. > >>> > >>> I agree that it is much less elegant than a VLA. This is in preparation > >>> for DPDK on Windows, which using the Microsoft Visual C++ (MSVC) compiler. > >>> MSVC does not support variable length arrays. It does, however, support > >>> alloca(), as does GCC/ICC. > >>> > >>> For this particular instance, the point is moot, since the function is > >>> not used anywhere and can just as easily be removed. Though it does not > >>> address the issue for the ~100 other instances where VLAs are used. We > >>> will be submitting patches for those as more common files are ported to > >>> Windows. > >> > >> If Microsoft's C compiler doesn't support C99, some 20 years after its > >> release, maybe it's time to find a new compiler, instead of messing up > >> the DPDK code in a ~100 instances. > > > > If think there is no reasonnable compiler for Windows. > > Yes I know, it's crazy. > > > With's wrong with the Windows version of Clang?
I agree it should be the preferred compiler for DPDK on Windows. But Microsoft told there are some issues working with clang. Jason, Harini, please, could you elaborate?
