Build fails with LLVM clang

[rouson]

I'm running ./install.sh with the following compiler:

% clang --version
clang version 19.0.0git (git@github.com:llvm/llvm-project 325f51237252e6dab8e4e1ea1fa7acbb4faee1cd)
Target: arm64-apple-darwin23.3.0
Thread model: posix
InstalledDir: /Users/rouson/Repositories/llvm-project/build/bin

and with the flang-new and clang++ in the same path. The build fails with the error messages below:

** % ./install.sh 
PREFIX=/Users/rouson/.local/bin
PKG_CONFIG_PATH=/Users/rouson/.local/bin/lib/pkgconfig
Initialized empty Git repository in /Users/rouson/Repositories/caffeine/build/dependencies/veggies/.git/
warning: redirecting to https://gitlab.com/everythingfunctional/veggies.git/
remote: Enumerating objects: 120, done.
remote: Counting objects: 100% (120/120), done.
remote: Compressing objects: 100% (101/101), done.
remote: Total 120 (delta 55), reused 36 (delta 15), pack-reused 0
Receiving objects: 100% (120/120), 104.81 KiB | 20.96 MiB/s, done.
Resolving deltas: 100% (55/55), done.
From https://gitlab.com/everythingfunctional/veggies
 * tag               v1.0.5     -> FETCH_HEAD
Initialized empty Git repository in /Users/rouson/Repositories/caffeine/build/dependencies/iso_varying_string/.git/
remote: Enumerating objects: 77, done.
remote: Counting objects: 100% (77/77), done.
remote: Compressing objects: 100% (41/41), done.
remote: Total 77 (delta 33), reused 50 (delta 24), pack-reused 0
Unpacking objects: 100% (77/77), 35.68 KiB | 410.00 KiB/s, done.
From https://gitlab.com/everythingfunctional/iso_varying_string
 * tag               v3.0.4     -> FETCH_HEAD
Initialized empty Git repository in /Users/rouson/Repositories/caffeine/build/dependencies/strff/.git/
remote: Enumerating objects: 31, done.
remote: Counting objects: 100% (31/31), done.
remote: Compressing objects: 100% (26/26), done.
remote: Total 31 (delta 6), reused 22 (delta 2), pack-reused 0
Unpacking objects: 100% (31/31), 19.44 KiB | 485.00 KiB/s, done.
From https://gitlab.com/everythingfunctional/strff
 * tag               v3.1.1     -> FETCH_HEAD
prif.f90                               done.
program_termination.c                  done.
caffeine_h_m.f90                       done.
utilities_m.f90                        done.
caffeine.c                             failed.
[ 12%] Compiling...
././src/caffeine/caffeine.c:73:7: error: call to undeclared function 'caf_this_image'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
   73 |   if (caf_this_image(myworldteam) == 1) {
      |       ^
././src/caffeine/caffeine.c:74:47: error: incompatible integer to pointer conversion passing 'intptr_t' (aka 'long') to parameter of type 'void *' [-Wint-conversion]
   74 |     *symmetric_heap = create_mspace_with_base(*symmetric_heap_start, symmetric_heap_size, 0);
      |                                               ^~~~~~~~~~~~~~~~~~~~~
././src/caffeine/../dlmalloc/dl_malloc.h:564:38: note: passing argument to parameter 'base' here
  564 | mspace create_mspace_with_base(void* base, size_t capacity, int locked);
      |                                      ^
././src/caffeine/caffeine.c:77:49: error: incompatible integer to pointer conversion passing 'intptr_t' (aka 'long') to parameter of type 'void *' [-Wint-conversion]
   77 |   *non_symmetric_heap = create_mspace_with_base(non_symmetric_heap_start, non_symmetric_heap_size, 0);
      |                                                 ^~~~~~~~~~~~~~~~~~~~~~~~
././src/caffeine/../dlmalloc/dl_malloc.h:564:38: note: passing argument to parameter 'base' here
  564 | mspace create_mspace_with_base(void* base, size_t capacity, int locked);
      |                                      ^
././src/caffeine/caffeine.c:142:103: warning: incompatible pointer types passing 'gex_Coll_ReduceFn_t *' (aka 'void (**)(const void *, void *, unsigned long, const void *)') to parameter of type 'gex_Coll_ReduceFn_t' (aka 'void (*)(const void *, void *, unsigned long, const void *)'); dereference with * [-Wincompatible-pointer-types]
  142 |       team, result_image-1, a_address, a_address, GEX_DT_USER, c_sizeof_a, num_elements, GEX_OP_USER, user_op, &c_sizeof_a, 0
      |                                                                                                       ^~~~~~~
      |                                                                                                       *
/Users/rouson/.local/bin/include/gasnet_coll.h:400:60: note: expanded from macro 'gex_Coll_ReduceToOneNB'
  400 |         gasnete_tm_reduce_nb(tm,root,dst,src,dt,dts,dtc,op,fn,cdata,flags,0 GASNETI_THREAD_GET)
      |                                                            ^~
/Users/rouson/.local/bin/include/gasnet_coll.h:396:58: note: passing argument to parameter '_user_op' here
  396 |                        gex_OP_t _op, gex_Coll_ReduceFn_t _user_op, void * _user_cdata,
      |                                                          ^
././src/caffeine/caffeine.c:146:103: warning: incompatible pointer types passing 'gex_Coll_ReduceFn_t *' (aka 'void (**)(const void *, void *, unsigned long, const void *)') to parameter of type 'gex_Coll_ReduceFn_t' (aka 'void (*)(const void *, void *, unsigned long, const void *)'); dereference with * [-Wincompatible-pointer-types]
  146 |       team,                 a_address, a_address, GEX_DT_USER, c_sizeof_a, num_elements, GEX_OP_USER, user_op, &c_sizeof_a, 0
      |                                                                                                       ^~~~~~~
      |                                                                                                       *
/Users/rouson/.local/bin/include/gasnet_coll.h:413:59: note: expanded from macro 'gex_Coll_ReduceToAllNB'
  413 |         gasnete_tm_reduce_all_nb(tm,dst,src,dt,dts,dtc,op,fn,cdata,flags,0 GASNETI_THREAD_GET)
      |                                                           ^~
/Users/rouson/.local/bin/include/gasnet_coll.h:409:59: note: passing argument to parameter '_user_op' here
  409 |                         gex_OP_t _op, gex_Coll_ReduceFn_t _user_op, void * _user_cdata,
      |                                                           ^
././src/caffeine/caffeine.c:178:14: warning: assigning to 'char *' from 'const char *' discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers]
  178 |       errmsg = return_message;
      |              ^ ~~~~~~~~~~~~~~
././src/caffeine/caffeine.c:259:10: warning: overflow converting case value to switch condition type (4100 to 4) [-Wswitch]
  259 |     case double_Complex_workaround: a_type = GEX_DT_DBL; num_elements *= 2; c_sizeof_a /= 2; break;
      |          ^
././src/caffeine/caffeine.c:258:10: warning: overflow converting case value to switch condition type (2052 to 4) [-Wswitch]
  258 |     case float_Complex_workaround:  a_type = GEX_DT_FLT; num_elements *= 2; c_sizeof_a /= 2; break;
      |          ^
././src/caffeine/caffeine.c:298:10: warning: overflow converting case value to switch condition type (4100 to 4) [-Wswitch]
  298 |     case double_Complex_workaround: return true;
      |          ^
././src/caffeine/caffeine.c:297:10: warning: overflow converting case value to switch condition type (2052 to 4) [-Wswitch]
  297 |     case float_Complex_workaround:  return true;
      |          ^
7 warnings and 3 errors generated.
<ERROR> Compilation failed for object " src_caffeine_caffeine.c.o "
<ERROR> stopping due to failed compilation
STOP 1
**

[bonachea]

This looks like an example of a defect predicted by issue #70

Specifically gcc defaults to more permissive behavior than clang, resulting in warnings and errors when compiling with the latter.

[rouson]

@bonachea so possibly my initial comment in this issue should be moved to #70 and this one closed or maybe we keep this one open as a LLVM clang-specific issue. The other issue could be our catch-all issue tied to the specific ones by hash-tag links.

[bonachea]

I'm not saying you should close this issue, which indicates a real defect in our clang support.

This just adds motivation for resolving issue #70 by adding some CI that exercises LLVM (which will fail until we fix the current issue).

[ktras]

Also related to issue #74.