Re: virtualbon-ose-kmod build fails with 14-CURRENT and llvm15

On Mon, Feb 27, 2023 at 10:27 AM Brooks Davis <brooks@freebsd.org> wrote:

> On Sun, Feb 26, 2023 at 09:45:34AM -0800, Kevin Oberman wrote:
> > I updated my system yesterday. I then tried to rebuild
> virtualbox-ose-kmod.
> > This fails under llvm15. The same source code built successfully with
> > llvm14, so I assume that the code has a problem with 15. I suspect that
> 15
> > changed some default and declared this as an error, but may be "fixed"
> with
> > the proper build option.
> >
> > Here is the command and error that I see:
> >
> > cc  -O2 -pipe -fno-strict-aliasing -DRT_OS_FREEBSD -DIN_RING0 -DIN_RT_R0
> > -DIN_SUP_R0 -DSUPDRV_WITH_RELEASE_LOGGER -DVBOX -DRT_WITH_VBOX -w
> > -DVBOX_WITH_HARDENING -DVBOX_WITH_64_BITS_GUESTS -DRT_ARCH_AMD64  -Werror
> > -D_KERNEL -DKLD_MODULE -nostdinc  -Iinclude -I. -Ir0drv -include
> >
> /usr/ports/emulators/virtualbox-ose-kmod/work/VirtualBox-6.1.36/out/freebsd.amd64/release/bin/src/vboxdrv/opt_global.h
> > -I. -I/usr/src/sys -I/usr/src/sys/contrib/ck/include -fno-common
> >  -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer
> > -fdebug-prefix-map=./machine=/usr/src/sys/amd64/include
> > -fdebug-prefix-map=./x86=/usr/src/sys/x86/include
> > -fdebug-prefix-map=./i386=/usr/src/sys/i386/include     -MD
> >  -MF.depend.SUPDrv-freebsd.o -MTSUPDrv-freebsd.o -mcmodel=kernel
> > -mno-red-zone -mno-mmx -mno-sse -msoft-float
> >  -fno-asynchronous-unwind-tables -ffreestanding -fwrapv -fstack-protector
> > -Wall -Wnested-externs -Wstrict-prototypes -Wmissing-prototypes
> > -Wpointer-arith -Wcast-qual -Wundef -Wno-pointer-sign
> > -D__printf__=__freebsd_kprintf__ -Wmissing-include-dirs
> > -fdiagnostics-show-option -Wno-unknown-pragmas
> > -Wno-error=tautological-compare -Wno-error=empty-body
> > -Wno-error=parentheses-equality -Wno-error=unused-function
> > -Wno-error=pointer-sign -Wno-error=shift-negative-value
> > -Wno-address-of-packed-member -Wno-error=array-parameter
> > -Wno-error=deprecated-non-prototype -Wno-error=strict-prototypes
> > -Wno-error=unused-but-set-variable -Wno-format-zero-length   -mno-aes
> > -mno-avx  -std=iso9899:1999 -c
> >
> /usr/ports/emulators/virtualbox-ose-kmod/work/VirtualBox-6.1.36/out/freebsd.amd64/release/bin/src/vboxdrv/freebsd/SUPDrv-freebsd.c
> > -o SUPDrv-freebsd.o
> >
> /usr/ports/emulators/virtualbox-ose-kmod/work/VirtualBox-6.1.36/out/freebsd.amd64/release/bin/src/vboxdrv/freebsd/SUPDrv-freebsd.c:433:50:
> > error: incompatible pointer to integer conversion passing 'void *' to
> > parameter of type 'RTR3PTR' (aka 'unsigned long') [-Wint-conversion]
> >         if (RT_FAILURE(RTR0MemUserCopyFrom(&Hdr, pvUser, sizeof(Hdr))))
> >                                                  ^~~~~~
> > include/iprt/errcore.h:99:58: note: expanded from macro 'RT_FAILURE'
> >
> > Any help appreciated. I really need virtualbox. I think I may force it to
> > build with llvm14, but I's prefer a fix to build with llvm15.
>
> Assuming the code works in practice, it should just be a matter of
> adding a cast (void *)(uintptr_t)pvUser.
>
> -- Brooks
>

Thanks to both of you. Fixing the code seems preferable to patching and
rebuilding llvm15, so I tried, but it made no difference, other than the
cast, but I may have truncated the error message too soon. Here is the
complete message after the patch:
/usr/ports/emulators/virtualbox-ose-kmod/work/VirtualBox-6.1.36/out/freebsd.amd64/release/bin/src/vboxdrv/freebsd/SUPDrv-freebsd.c:433:50:
error: incompatible pointer to integer conversion passing 'void *' to
parameter of type 'RTR3PTR' (aka 'unsigned long') [-Wint-conversion]
        if (RT_FAILURE(RTR0MemUserCopyFrom(&Hdr, (void *)(uintptr_t)pvUser,
sizeof(Hdr))))
                                                 ^~~~~~~~~~~~~~~~~~~~~~~~~
include/iprt/errcore.h:99:58: note: expanded from macro 'RT_FAILURE'
#define RT_FAILURE(rc)      ( RT_UNLIKELY(!RT_SUCCESS_NP(rc)) )
                                                         ^~
include/iprt/errcore.h:80:38: note: expanded from macro 'RT_SUCCESS_NP'
# define RT_SUCCESS_NP(rc)   ( (int)(rc) >= VINF_SUCCESS )
                                     ^~
include/iprt/cdefs.h:1826:53: note: expanded from macro 'RT_UNLIKELY'
#  define RT_UNLIKELY(expr)     __builtin_expect(!!(expr), 0)
                                                    ^~~~
include/iprt/mem.h:756:56: note: passing argument to parameter 'R3PtrSrc'
here
RTR0DECL(int) RTR0MemUserCopyFrom(void *pvDst, RTR3PTR R3PtrSrc, size_t cb);
                                                       ^

Please understand that I am not a C programmer.  Looking at this leaves me
a bit lost.
-- 
Kevin Oberman, Part time kid herder and retired Network Engineer
E-mail: rkoberman@gmail.com
PGP Fingerprint: D03FB98AFA78E3B78C1694B318AB39EF1B055683