with structuredAttrs lists will be bash arrays which cannot be exported
which will be a issue with some patches and some wrappers like cc-wrapper
this makes it clearer that NIX_CFLAGS_COMPILE must be a string as lists
in env cause a eval failure
Without the change build on `master` fails as:
jma/jma.h:67:28: error: ISO C++17 does not allow dynamic exception specifications
67 | jma_open(const char *) throw(jma_errors);
| ^~~~~
ZHF: https://github.com/NixOS/nixpkgs/issues/199919
Workaround build failure on -fno-common toolchains like upstream
gcc-10. Otherwise build fails as:
ld: initc.o:(.bss+0x28): multiple definition of `HacksDisable'; cfg.o:(.bss+0x59e3): first defined here
