gnum4: unconditionally disable format hardening

[alyssais]

The use of hardeningDisable was incomplete, as it also affected musl and probably other configurations. Regardless, it's better to actually fix the issue than ignoring it, especially because it's difficult to notice in future when hardeningDisable entries are no longer necessary.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• Nixpkgs 25.11 Release Notes (or backporting 24.11 and 25.05 Nixpkgs Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
• NixOS 25.11 Release Notes (or backporting 24.11 and 25.05 NixOS Release notes)
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md, pkgs/README.md, maintainers/README.md and other contributing documentation in corresponding paths.

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[alyssais]

Hmm, this doesn't seem to work on Darwin.

[emilazy]

  CC       libm4_a-clean-temp.o
  CC       libm4_a-clean-temp-simple.o
clean-temp.c:235:14: error: format string is not a string literal (potentially insecure) [-Werror,-Wformat-security]
  234 |       error (0, errno,
      |       ~~~~~~~~~~~~~~~~
  235 |              _("cannot find a temporary directory, try setting $TMPDIR"));
      |              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
clean-temp.c:69:18: note: expanded from macro '_'
   69 | #define _(msgid) dgettext ("gnulib", msgid)
      |                  ^
./gettext.h:94:39: note: expanded from macro 'dgettext'
   94 | #  define dgettext(Domainname, Msgid) ((void) (Domainname), gettext (Msgid))
      |                                       ^
./error.h:496:39: note: expanded from macro 'error'
  496 |       __gl_error_call (error, status, __VA_ARGS__)
      |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~
./error.h:432:44: note: expanded from macro '__gl_error_call'
  432 |      ? __gl_error_call1 (function, status, __VA_ARGS__)         \
      |        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~
./error.h:421:26: note: expanded from macro '__gl_error_call1'
  421 |     ((function) (status, __VA_ARGS__), \
      |                          ^~~~~~~~~~~
clean-temp.c:235:14: note: treat the string as an argument to avoid this
  235 |              _("cannot find a temporary directory, try setting $TMPDIR"));
      |              ^
      |              "%s",
clean-temp.c:69:18: note: expanded from macro '_'
   69 | #define _(msgid) dgettext ("gnulib", msgid)
      |                  ^
./gettext.h:94:39: note: expanded from macro 'dgettext'
   94 | #  define dgettext(Domainname, Msgid) ((void) (Domainname), gettext (Msgid))
      |                                       ^
./error.h:496:39: note: expanded from macro 'error'
  496 |       __gl_error_call (error, status, __VA_ARGS__)
      |                                       ^
./error.h:432:44: note: expanded from macro '__gl_error_call'
  432 |      ? __gl_error_call1 (function, status, __VA_ARGS__)         \
      |                                            ^
./error.h:421:26: note: expanded from macro '__gl_error_call1'
  421 |     ((function) (status, __VA_ARGS__), \
      |                          ^
clean-temp.c:235:14: error: format string is not a string literal (potentially insecure) [-Werror,-Wformat-security]
234 |       error (0, errno,
      |       ~~~~~~~~~~~~~~~~
  235 |              _("cannot find a temporary directory, try setting $TMPDIR"));
      |              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
clean-temp.c:69:18: note: expanded from macro '_'
   69 | #define _(msgid) dgettext ("gnulib", msgid)
      |                  ^
./gettext.h:94:39: note: expanded from macro 'dgettext'
   94 | #  define dgettext(Domainname, Msgid) ((void) (Domainname), gettext (Msgid))
      |                                       ^
./error.h:496:39: note: expanded from macro 'error'
  496 |       __gl_error_call (error, status, __VA_ARGS__)
      |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~
./error.h:436:51: note: expanded from macro '__gl_error_call'
  436 |          __gl_error_call1 (function, __errstatus, __VA_ARGS__); \
      |          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~
./error.h:421:26: note: expanded from macro '__gl_error_call1'
  421 |     ((function) (status, __VA_ARGS__), \
      |                          ^~~~~~~~~~~
clean-temp.c:235:14: note: treat the string as an argument to avoid this
  235 |              _("cannot find a temporary directory, try setting $TMPDIR"));
      |              ^
      |              "%s",
clean-temp.c:69:18: note: expanded from macro '_'
   69 | #define _(msgid) dgettext ("gnulib", msgid)
      |                  ^
./gettext.h:94:39: note: expanded from macro 'dgettext'
   94 | #  define dgettext(Domainname, Msgid) ((void) (Domainname), gettext (Msgid))
      |                                       ^
./error.h:496:39: note: expanded from macro 'error'
  496 |       __gl_error_call (error, status, __VA_ARGS__)
      |                                       ^
./error.h:436:51: note: expanded from macro '__gl_error_call'
  436 |          __gl_error_call1 (function, __errstatus, __VA_ARGS__); \
      |                                                   ^
./error.h:421:26: note: expanded from macro '__gl_error_call1'
  421 |     ((function) (status, __VA_ARGS__), \
      |                          ^

I don’t know why they’re excluding Clang here or really what on earth they’re doing in general but I can confirm that it does not work on Darwin.

[alyssais]

So seems like we still need hardeningDisable for Clang (not necessarily Darwin). Updated.

[alyssais]

Well, given that checking what compiler we're using causes infinite recursion (at least until #365057), I think unconditionally disabling format hardening is actually the best we can do :(