2.40 build failure

[chenrui333]

👋 trying to build the latest release, but run into some build issue. The error log is as below:

error build log

  libuuid/src/uuid_time.c:89:87: error: aliases are not supported on darwin
  extern time_t uuid_time(const uuid_t uu, struct timeval *ret_tv) __attribute__((weak, alias("__uuid_time")));
                                                                                        ^
  1 error generated.

full build log, https://github.com/Homebrew/homebrew-core/actions/runs/8476769739/job/23226791433?pr=167458
relates to Homebrew/homebrew-core#167458

[jwillikers]

I hit this issue for macOS as well using Meson.

[gershnik]

One way to fix this:

--- libuuid/src/uuid_time.c
+++ libuuid/src/uuid_time.c
@@ -85,6 +85,10 @@
 }
 #if defined(__USE_TIME_BITS64) && defined(__GLIBC__)
 extern time_t uuid_time64(const uuid_t uu, struct timeval *ret_tv) __attribute__((weak, alias("__uuid_time")));
+#elif defined(__clang__) && defined(__APPLE__)
+__asm__(".globl _uuid_time");
+__asm__(".set _uuid_time, ___uuid_time");
+extern time_t uuid_time(const uuid_t uu, struct timeval *ret_tv);
 #else
 extern time_t uuid_time(const uuid_t uu, struct timeval *ret_tv) __attribute__((weak, alias("__uuid_time")));
 #endif

[jwillikers]

@gershnik Would you want to submit a PR?

[gershnik]

@jwillikers My fix fixes the surface issue - the build no longer breaks and uuid_time is aliased to __uuid_time on Darwin but I have only a hazy understanding of the intent behind the uuid_time changes in 2.40 to be able to say "this is how this should actually be fixed".

For example why usage of uuid_time64 is tied to __GLIBC__? Shouldn't something equivalent be also available for libc++ and Darwin?

Thus my comment was meant to unblock people who need the build not to break rather than to suggest a proper fix. (FWIW I maintain a CMake build of libuuid at https://github.com/gershnik/libuuid-cmake and the fix works there)

If the libuuid library authors agree that this is actually the proper fix, happy to submit a PR.