Thanks for your response. > Not having access to that specific version of LwIP
The line is actually part of the latest stable version (2.0.2). It just moved a few lines up: https://git.savannah.gnu.org/cgit/lwip.git/tree/src/core/ipv4/ip4_frag.c?h=S TABLE-2_0_2_RELEASE_VER#n322 > The only way the compiler can KNOW you're not dereferencing > a null pointer is for you to check for null explicitly first Yes, you are right. When adding the additional check, the warning disappears. This feels to me like the best solution, since assertions do not have to be enabled in every case and they do not implement real error handling. One additional note: If the check is not there and assertions are disabled, gcc may insert an undefined instruction "udf" (or 0xdeff). I am working with an Cortex-M7 controller. If executed, the instruction will cause an HardFault for an undefined instruction. I stumbled over this issue, by searching for this instruction in the disassembly. This is the only location in lwIP, where I found this issue. I would really like to get rid of this invalid instruction, since this feels to me like a bug, even if it will never be executed... Best regards, Andreas PS: Can you please keep me in CC, so that I am able to answer directly to messages? _______________________________________________ lwip-users mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/lwip-users
