Applications fail to build when using both musl and lwip with memory pools

[Mihnea27]

Describe the bug

Applications fail to build when configured to use lib-musl and lib-lwip with memory pools (CONFIG_LWIP_POOLS=y).

Steps to reproduce

1. Write a basic helloworld application, use Unikraft version 0.16.1 and lib-musl and lib-lwip staging versions.
2. In the configuration set:

• x86 as architecture (CONFIG_ARCH_x86_64=y)
• KVM as platform with qemu as VMM (CONFIG_PLAT_KVM=y and CONFIG_KVM_VMM_QEMU=y)
• use lib-musl (CONFIG_LIBMUSL=y)
• use lib-lwip (CONFIG_LIBLWIP=y) with memory pools (CONFIG_LWIP_POOLS=y)

3. Try to build the application with make

Expected behavior

Application builds successfully.

Which architectures were you using or does this bug affect?

x86_64

Which platforms were you using or does this bug affect?

kvm

Relevant log output

[...]
/home/mihnea27/unikernels/build_error/app-helloworld/build/liblwip/origin/fork-lwip-UNIKRAFT-2_1_x/src/include/lwip/priv/memp_std.h:31:53: note: in expansion of macro ‘LWIP_MEMPOOL’
   31 | #define LWIP_PBUF_MEMPOOL(name, num, payload, desc) LWIP_MEMPOOL(name, num, (LWIP_MEM_ALIGN_SIZE(sizeof(struct pbuf)) + LWIP_MEM_ALIGN_SIZE(payload)), desc)
      |                                                     ^~~~~~~~~~~~
/home/mihnea27/unikernels/build_error/app-helloworld/build/liblwip/origin/fork-lwip-UNIKRAFT-2_1_x/src/include/lwip/priv/memp_std.h:134:1: note: in expansion of macro ‘LWIP_PBUF_MEMPOOL’
  134 | LWIP_PBUF_MEMPOOL(PBUF_POOL, PBUF_POOL_SIZE,           PBUF_POOL_BUFSIZE,             "PBUF_POOL")
      | ^~~~~~~~~~~~~~~~~
/home/mihnea27/git/unikraft_libs/lib-lwip/include/lwipopts.h:275:24: note: in expansion of macro ‘MAX’
  275 | #define PBUF_POOL_SIZE MAX(((TCP_WND + TCP_MSS - 1) / TCP_MSS), 2 * IP_REASS_MAX_PBUFS)
      |                        ^~~
/home/mihnea27/unikernels/build_error/app-helloworld/build/liblwip/origin/fork-lwip-UNIKRAFT-2_1_x/src/include/lwip/priv/memp_std.h:134:30: note: in expansion of macro ‘PBUF_POOL_SIZE’
  134 | LWIP_PBUF_MEMPOOL(PBUF_POOL, PBUF_POOL_SIZE,           PBUF_POOL_BUFSIZE,             "PBUF_POOL")
      |                              ^~~~~~~~~~~~~~
/home/mihnea27/git/unikraft/include/uk/essentials.h:77:9: error: braced-group within expression allowed only inside a function
   77 |         ({                                                                     \
      |         ^
/home/mihnea27/unikernels/build_error/app-helloworld/build/liblwip/origin/fork-lwip-UNIKRAFT-2_1_x/src/include/lwip/arch.h:287:40: note: in definition of macro ‘LWIP_MEM_ALIGN_BUFFER’
  287 | #define LWIP_MEM_ALIGN_BUFFER(size) (((size) + MEM_ALIGNMENT - 1U))
[...]