isync build fails: error: expected ')' before '<=' token

[barracuda156]

Making all in src
make[2]: Entering directory `/opt/local/var/macports/build/isync-9926d506/work/isync-1.5.1/src'
/opt/local/bin/gcc-mp-14 -DHAVE_CONFIG_H -I. -I..   -I/opt/local/include -I/opt/local/include/db62 -D_GNU_SOURCE -I/opt/local/libexec/openssl3/include   -pipe -Os -arch ppc -pipe -std=c11 -pedantic -Wall -Wextra -Wshadow -Wcast-qual -Wformat=2 -Wformat-signedness -Wformat-nonliteral -Wstrict-prototypes -Wno-overlength-strings -MT util.o -MD -MP -MF .deps/util.Tpo -c -o util.o util.c
/opt/local/bin/gcc-mp-14 -DHAVE_CONFIG_H -I. -I..   -I/opt/local/include -I/opt/local/include/db62 -D_GNU_SOURCE -I/opt/local/libexec/openssl3/include   -pipe -Os -arch ppc -pipe -std=c11 -pedantic -Wall -Wextra -Wshadow -Wcast-qual -Wformat=2 -Wformat-signedness -Wformat-nonliteral -Wstrict-prototypes -Wno-overlength-strings -MT config.o -MD -MP -MF .deps/config.Tpo -c -o config.o config.c
In file included from config.h:11,
                 from config.c:10:
common.h:92:40: error: expected ')' before '<=' token
   92 |         static_assert( list##_num_bits <= sizeof(((type){ 0 }).field) * 8, \
      |                                        ^~
driver.h:81:1: note: in expansion of macro 'static_assert_bits'
   81 | static_assert_bits(msg_flags_enum, message_t, flags);
      | ^~~~~~~~~~~~~~~~~~
common.h:92:40: error: expected ')' before '<=' token
   92 |         static_assert( list##_num_bits <= sizeof(((type){ 0 }).field) * 8, \
      |                                        ^~
driver.h:82:1: note: in expansion of macro 'static_assert_bits'
   82 | static_assert_bits(msg_sts_enum, message_t, status);
      | ^~~~~~~~~~~~~~~~~~
common.h:92:40: error: expected ')' before '<=' token
   92 |         static_assert( list##_num_bits <= sizeof(((type){ 0 }).field) * 8, \
      |                                        ^~
driver.h:124:1: note: in expansion of macro 'static_assert_bits'
  124 | static_assert_bits(msg_flags_enum, msg_data_t, flags);
      | ^~~~~~~~~~~~~~~~~~
util.c: In function 'memrchr':
util.c:457:21: warning: cast discards 'const' qualifier from pointer target type [-Wcast-qual]
  457 |         u_char *b = (u_char *)s, *e = b + n;
      |                     ^
make[2]: *** [config.o] Error 1
make[2]: *** Waiting for unfinished jobs....
mv -f .deps/util.Tpo .deps/util.Po
make[2]: Leaving directory `/opt/local/var/macports/build/isync-9926d506/work/isync-1.5.1/src'
make[1]: *** [all-recursive] Error 1