<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/86744>86744</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
Missing header `omp.h` in install directory when building `llvm@18.1.2` with `openmp` as runtime with `cmake@3.29.0`
</td>
</tr>
<tr>
<th>Labels</th>
<td>
new issue
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
s-sajid-ali
</td>
</tr>
</table>
<pre>
### Summary
When installing `llvm@18.1.2` with `spack` using `cmake@3.29.0` and configuring `openmp` to be enabled as a runtime, the final install directory is missing `omp.h` even though the header is present in the build directory. However, this problem does not occur when building `llvm@18.1.2` with the same configuration using `cmake@3.27.9`.
### Details
Here are the two builds of `llvm@18.1.2` differing only in the version of `cmake` used for the build.
```
sasyed@MAC-140753 ~> spack find -lv llvm
-- darwin-sonoma-m1 / apple-clang@15.0.0 ------------------------
cgcsya3 llvm@18.1.2+clang~code_signing~cuda~flang~gold~ipo~libomptarget~libomptarget_debug~link_llvm_dylib+lld+lldb+llvm_dylib+lua~mlir+polly~python~split_dwarf~z3~zstd build_system=cmake build_type=Release compiler-rt=runtime generator=ninja libcxx=runtime libunwind=runtime openmp=runtime shlib_symbol_version=none targets=none version_suffix=none
bydpwmd llvm@18.1.2+clang~code_signing~cuda~flang~gold~ipo~libomptarget~libomptarget_debug~link_llvm_dylib+lld+lldb+llvm_dylib+lua~mlir+polly~python~split_dwarf~z3~zstd build_system=cmake build_type=Release compiler-rt=runtime generator=ninja libcxx=runtime libunwind=runtime openmp=runtime shlib_symbol_version=none targets=none version_suffix=none
==> 2 installed packages
sasyed@MAC-140753 ~> spack diff /cgc /byd
==> Warning: This interface is subject to change.
--- llvm@18.1.2/cgcsya36nknpeizproew2cdxtf4r6xcb
+++ llvm@18.1.2/bydpwmdkng7shunf3ltzj56a3bkjepy5
@@ hash @@
- cmake slpmwq3esyyjikfqskqbea3nvobw7oei
+ cmake yyb45mfiot4obxxx7kashbrpvudmx3d4
- llvm cgcsya36nknpeizproew2cdxtf4r6xcb
+ llvm bydpwmdkng7shunf3ltzj56a3bkjepy5
@@ package_hash @@
- cmake gsj2wl26n5psfanwtf3a3owh6fcj5mnx6eyuygm6g7eo5wye6y4a====
+ cmake 4nfzzuirvovagbkvkxjvtkvwyokgaekv3iyo3emo7h2ai42uofmq====
@@ version @@
- cmake 3.29.0
+ cmake 3.27.9
sasyed@MAC-140753 ~>
```
Here are the results of an attempt to locate `omp.h` within the two install destinations:
```
sasyed@MAC-140753 ~> fd "omp.h" (spack location -i /cgc)
/Users/sasyed/Documents/packages/spack/opt/spack/darwin-sonoma-m1/apple-clang-15.0.0/llvm-18.1.2-cgcsya36nknpeizproew2cdxtf4r6xcb/include/llvm/Frontend/OpenMP/OMP.h.inc
/Users/sasyed/Documents/packages/spack/opt/spack/darwin-sonoma-m1/apple-clang-15.0.0/llvm-18.1.2-cgcsya36nknpeizproew2cdxtf4r6xcb/include/polly/CodeGen/LoopGeneratorsGOMP.h
sasyed@MAC-140753 ~> fd "omp.h" (spack location -i /byd)
/Users/sasyed/Documents/packages/spack/opt/spack/darwin-sonoma-m1/apple-clang-15.0.0/llvm-18.1.2-bydpwmdkng7shunf3ltzj56a3bkjepy5/include/c++/v1/__algorithm/comp.h
/Users/sasyed/Documents/packages/spack/opt/spack/darwin-sonoma-m1/apple-clang-15.0.0/llvm-18.1.2-bydpwmdkng7shunf3ltzj56a3bkjepy5/include/llvm/Frontend/OpenMP/OMP.h.inc
/Users/sasyed/Documents/packages/spack/opt/spack/darwin-sonoma-m1/apple-clang-15.0.0/llvm-18.1.2-bydpwmdkng7shunf3ltzj56a3bkjepy5/include/polly/CodeGen/LoopGeneratorsGOMP.h
/Users/sasyed/Documents/packages/spack/opt/spack/darwin-sonoma-m1/apple-clang-15.0.0/llvm-18.1.2-bydpwmdkng7shunf3ltzj56a3bkjepy5/lib/clang/18/include/omp.h
sasyed@MAC-140753 ~>
```
where it is clear that when using `cmake@3.29.0` the header `omp.h` is missing.
It is however, present in the build directory as shown below:
```
sasyed@MAC-140753 /v/f/m/z/T/s/s/s/spack-build-cgcsya3> pwd
/var/folders/mb/zd6pgmt100q77s5fhn5xf4jw0000gq/T/sasyed/spack-stage/spack-stage-llvm-18.1.2-cgcsya36nknpeizproew2cdxtf4r6xcb/spack-build-cgcsya3
sasyed@MAC-140753 /v/f/m/z/T/s/s/s/spack-build-cgcsya3> fd "omp.h"
include/c++/v1/__algorithm/comp.h
include/llvm/Frontend/OpenMP/OMP.h.inc
runtimes/runtimes-bins/openmp/runtime/src/omp.h
sasyed@MAC-140753 /v/f/m/z/T/s/s/s/spack-build-cgcsya3>
```
### Platform information & Supporting logs
Output of `spack debug report`:
```
sasyed@MAC-140753 ~> spack debug report
* **Spack:** 0.22.0.dev0 (69509a6d9a9c515dc4e00fbfe94c7e27a440b0ad)
* **Python:** 3.9.6
* **Platform:** darwin-sonoma-m1
* **Concretizer:** clingo
sasyed@MAC-140753 ~>
```
Build log for `llvm@18.1.2 targets=none ^cmake@3.29.0`: [spack-build-out.txt](https://github.com/llvm/llvm-project/files/14765311/spack-build-out.txt)
Build log for `llvm@18.1.2 targets=none` (implicitly picking `cmake@3.27.9`): [spack-build-out.txt](https://github.com/llvm/llvm-project/files/14765315/spack-build-out.txt)
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzsWEtv4zgS_jXMhZAgUw_HBx-SdqtngW1MY3sWczQosSQxpkiFpCwrB__2BSk5dtLuRxo7mBlgAkUWX8V6fsUiNYbXEmCN0nuUbm5obxul1yYw9IGzgAp-Uyg2rhGJpwd_7tuW6hFFGxTd_d6AxFwaS4XgssYoi4TYtyiJFrfhIiQoi_DAbeMGTEfLnevozTy1bOkOUBLFIVmFkRuikuFSyYrXvZ4nqQ5k27lBq3ABGCQtBDBMDaZY99LyFhB5h20DuOKSihM_mHENpVV6xNzglpvTtqrtwsYRhD1IbBvV141f3gBloN3sToMBaTGXfqDouWBneiH-RQ2wBz3t6-erQkCLmQKDpbJYlWWv8eDU4xd_UzluC0NbeBadWq7kVT0twxXKohBP6p_fz7bZgKVcmKn7F9CAqQZP3g5qYsRgVV3lhPGqAq90JcV4knwP2jhepkUTI96EwHCl9Fk7zyxl0fz4pqFmBIaS6OPdu2CRRMs0xkcUv8feG5zBGA7EHnt2_IogwIzqgcvAKKlaGrQLjEiOadcJCEpBZe34TsMojHDwlb-JVFmXZqQxfikrufdEjqVisHXez12jZ_RY-f5aCXbknToKXqi2s1TXYF80tgyKvj4KLndbR3vLRsELRO6FYNN7alyO9PTYCq4Rue-UEOOxG22j5NF0gtstG6iujk_x8clYNulza0ZjoUXxxit97rRjByje_AcEUOP8pe24AB1oi-LNHAy4BgmaWqVRvJFcPlAseFEeDhdTBC96OXDJLvrmQDt3mEbwYmvGtlBiOzuCI6kk4EkR5tScR7emryp-mHsnIxQj64aW_WOEP9MIKN745z0mJ3gEhl0I0hrMD4WqwwcXiGVdup9iZK9J_061MyOK7_BvDhS5tKArWoJDVNMXD1BaB-JlQ2UN4SWEBUHw2kHyOXozuZMd8KdOKxhIyQ62SnR2KIsT-N1PzxfrZ8fbyXppml5WsbBPD2lG42L3AN2YzuuTCCURbqhp8PQ9c4TxZHMjunZ4jMGM4wPfVY9m91gAjeVeFcNSAX9m47RgHIskbSuubKKKw-Gw3FHTFLrb96w9xCx5pu8Yxj8s5Tz_TVLNBt5-XbraPJBBkEymnamoHGwV01gNTVaVD2krDxmM_Vi3Wb0ElQ4jZGNCTxb3z2vpE1k9PfVc79We1sVuvzs87O1uP4xqV1PY7WM-qhhatWwI5QnpVdU-XiE48X_KPldZn08NrxmYk-Q3XfpqqrqSNTWYXlifMqnE1FpoO-_CQpXUwovDhMvkc9J0yfb5EALGcukTunGR8bYsWTGMCJn2IAQjcjsFo9_faSbgc0wisjqpIv-vAW0QyWeyJN-osm9BWtf5HPQkn05kJFedvWi9zr6I5Be5N5gyLyK5c8dgirbgu15Mci5L0TOYFyKS51pJC9Lx92sH8uMn9_HxU9iEXJZ_F1l8HkEkf6cYfACJSP5vpboPJ_A3H7xE_x8rO8j9U638Xey51Ex5QuZ874hvt1TUSnPbONuXk7B_E1H-4g77Jlne4rB_VWn8aS6fSgGSL25fCHjhWV8NuKsgPDQO-rl1p5VSAHXFDbVTDfeNkvWicLxMB-eS82Wx9i9PvznXj98uNV2Zaxo1SFyAUAOK7344gbjIQySvEMmd9z4hkv_mbHP57-wU-C1PsOfU0w3s2QH2VDsiSrDJEVqn-ieWdXVrF1H0uFyatGpkeqiShyGKoqh-PG10cplpF2NpDS9bwRth9xq7f4D4L-F42uEncO1n8GM-9TvmTp9BwaXxkeUrg-cBx78uv-_wP6-Hb5ySzlcOnwS1ldIt5tL9TPkKkQx_7rtOaeviRqh6rjF-7W3X2_k2Ya4rXBmHNbjJbpc3ePhldXJJZWbxDiPifj57NIrvphaOQkLCKGSwj1yqzVZptKIZW9FVmS5SViYQRVVRwSopl0CWNEmiIqKXqfdE-JMvH8-U43AVZl9MmhV0nvYFKr5a8U7JUoPlT6DPi0rBZa1-Btem973HFaFqf23z-gLodSmJ0vdfIJ0_vab3l86iehvag0XpBpHbxtrOeIZzRPKa26YvwlK15wDw4d5p5QpB55JceE9fJMssjReLV554In7S-5skcBCMyC1vO8FLbsWIO17uvnaf5vb4g6VLvyPd5fuGrWO2ilf0BtaL5WKRrMgyITfNuigZRMu0iOMkWxAos1vK4oRGy7iogFTVDV-TiCRRTDJC4lVEwmLJCItoXMIKViRyTgMt5SJ03IZK1zfcmB7Wt9kySW4ELUAYfxdMiIQB-0EHgunmRq-9hEVfG5REghtrzlQstwLWH-dL1mv5UF65l_3B-9EXt8DUnG59nwe_TMo3vRbrN5vMS-ts5rXxvwAAAP__NTpcuw">