gromacs, gromacs-plumed @2021.3: error: expected identifier or '('

[ryandesign (Ryan Carsten Schmidt)]

gromacs:

​https://build.macports.org/builders/ports-10.6_x86_64-builder/builds/152575/steps/install-port/logs/stdio
​https://build.macports.org/builders/ports-10.6_i386-builder/builds/117085/steps/install-port/logs/stdio

gromacs-plumed:

​https://build.macports.org/builders/ports-10.6_x86_64-builder/builds/152576/steps/install-port/logs/stdio
​https://build.macports.org/builders/ports-10.6_i386-builder/builds/117086/steps/install-port/logs/stdio

In file included from /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_science_gromacs/gromacs-plumed/work/gromacs-2021.3/src/external/tng_io/src/compression/fixpoint.c:12:
/opt/local/include/libcxx/v1/math.h:316:8: error: expected identifier or '('
extern "C" {
       ^
1 error generated.