code in sbn/fsw/src/sbn_pack.h uses void *pointer arithmetic

While GCC allows it: It is non standard: The C standard does not allow void pointer arithmetic. However, GNU C is allowed by considering the size of void is 1.

C11 standard §6.2.5

Paragraph - 19

The void type comprises an empty set of values; it is an incomplete object type that cannot be completed.

Errors:

In file included from /home/maurice/source/cFS/apps/sbn/fsw/src/sbn_app.c:27:0:
cFS/apps/sbn/fsw/src/sbn_pack.h: In function "Pack_Data":
cFS/apps/sbn/fsw/src/sbn_pack.h:41:25: error: pointer of type "void *" used in arithmetic [-Werror=pointer-arith]
     memcpy(PackPtr->Buf + PackPtr->BufUsed, DataBuf, DataBufSz);

cFS/apps/sbn/fsw/src/sbn_pack.h: In function "Unpack_Data":
cFS/apps/sbn/fsw/src/sbn_pack.h:102:33: error: pointer of type "void *" used in arithmetic [-Werror=pointer-arith]
     memcpy(DataBuf, Unpack->Buf + Unpack->Curr, Sz);

cFS/apps/sbn/fsw/src/sbn_app.c: In function "SBN_PackMsg":
cFS/apps/sbn/fsw/src/sbn_app.c:134:26: error: pointer of type "void *" used in arithmetic [-Werror=pointer-arith]
         SwapCCSDS(SBNBuf + SBN_PACKED_HDR_SZ);

Used an example arch_build_custom.cmake

add_compile_options(
    -std=c99                # Target the C99 standard (without gcc extensions) 
    -pedantic               # Issue all the warnings demanded by strict ISO C
    -Wall                   # Warn about most questionable operations
    -Wstrict-prototypes     # Warn about missing prototypes
    -Wwrite-strings         # Warn if not treating string literals as "const"
    -Wpointer-arith         # Warn about suspicious pointer operations
    -Wcast-align            # Warn about casts that increase alignment requirements
    -Werror                 # Treat warnings as errors (code should be clean)
    -Wno-error=unused-but-set-variable
    -Wno-error=discarded-qualifiers
)

Fix is to fix the type of Buf from void to uint8 or remove the -Werror statement

Reporter Info Maurice Smulders, Geneva Technologies Inc

nasa / SBN

code in sbn/fsw/src/sbn_pack.h uses void *pointer arithmetic #16