From 546e5cfe45e38caae3607d732763608fd3b2f3f2 Mon Sep 17 00:00:00 2001
From: Rohit Goswami <rgoswami@ieee.org>
Date: Sun, 11 Oct 2026 10:45:42 -0500
Subject: [PATCH] Drop UCX --enable-optimizations for generic CPU targets

UCX's configure runs an AVX test program on the machine doing the build
when optimizations are enabled, and adds -mavx to the flags for the
whole package if it passes.
The x86_64/generic UCX installs in 2023.06, 2025.06 and 2026.06 all came
out with AVX in nearly every library.

Strip the option in a pre-configure hook when the target is one of the
generic ones or optarch is GENERIC, and check the configure line in the
hooks workflow.

See EESSI/software-layer#1778.
---
 .github/workflows/test-eb-hooks.yml | 49 +++++++++++++++++++++++++++++
 eb_hooks.py                         | 23 ++++++++++++++
 2 files changed, 72 insertions(+)

diff --git a/.github/workflows/test-eb-hooks.yml b/.github/workflows/test-eb-hooks.yml
index dfcc576c..a9cf6f21 100644
--- a/.github/workflows/test-eb-hooks.yml
+++ b/.github/workflows/test-eb-hooks.yml
@@ -168,3 +168,52 @@ jobs:
               # echo "$OUT" | grep -qiF 'add_property("arch","gpu")'
               # echo "$OUT" | grep -qiF 'setenv("EESSIROCMVERSION","6.4.1")'
               # echo "rompi toolchain handled"
+
+  check_ucx_generic_optimizations:
+    runs-on: ubuntu-24.04
+    strategy:
+      matrix:
+        include:
+          - EESSI_VERSION: '2023.06'
+            EASYCONFIG: 'UCX-1.15.0-GCCcore-13.2.0.eb'
+          - EESSI_VERSION: '2025.06'
+            EASYCONFIG: 'UCX-1.19.0-GCCcore-14.3.0.eb'
+
+    steps:
+        - name: Check out software-layer repository
+          uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+
+        - name: Mount EESSI CernVM-FS repository
+          uses: eessi/github-action-eessi@v3
+          with:
+            eessi_stack_version: ${{matrix.EESSI_VERSION}}
+            use_eessi_module: true
+
+        - name: Test that UCX is configured without --enable-optimizations for generic targets
+          if: ${{ github.event_name == 'pull_request' }}
+          run: |
+              module load EESSI-extend/${{matrix.EESSI_VERSION}}-easybuild
+
+              # print the ./configure command line of an extended dry run (eb wraps it at 80 columns)
+              configure_line() {
+                  eb --hooks=$PWD/eb_hooks.py --extended-dry-run "$@" ${{matrix.EASYCONFIG}} 2>&1 \
+                      | grep -A6 'running shell command "./configure' | tr -d '\n'
+              }
+
+              # the runner's own CPU target keeps the option
+              line=$(configure_line)
+              grep -q -- '--enable-cma' <<< "$line"
+              grep -q -- '--enable-optimizations' <<< "$line"
+              echo "Native target keeps --enable-optimizations"
+
+              for target in x86_64/generic aarch64/generic; do
+                  line=$(EESSI_SOFTWARE_SUBDIR=$target configure_line)
+                  grep -q -- '--enable-cma' <<< "$line"
+                  grep -q -- '--enable-optimizations' <<< "$line" && exit 1
+                  echo "$target drops --enable-optimizations"
+              done
+
+              line=$(configure_line --optarch=GENERIC)
+              grep -q -- '--enable-cma' <<< "$line"
+              grep -q -- '--enable-optimizations' <<< "$line" && exit 1
+              echo "--optarch=GENERIC drops --enable-optimizations"
diff --git a/eb_hooks.py b/eb_hooks.py
index fc26f88b..96330d2f 100644
--- a/eb_hooks.py
+++ b/eb_hooks.py
@@ -1674,6 +1674,28 @@ def pre_configure_hook_libfabric_disable_psm3_x86_64_generic(self, *args, **kwar
         raise EasyBuildError("libfabric-specific hook triggered for non-libfabric easyconfig?!")
 
 
+def pre_configure_hook_ucx_generic(self, *args, **kwargs):
+    """
+    Pre-configure hook for UCX: drop --enable-optimizations when building for a generic CPU target.
+    With that option, UCX's configure runs an AVX test program on the build host and adds -mavx to the
+    compiler flags of the whole package when it passes (on aarch64 it may add -mcpu for the build host);
+    UCX does not check the CPU at run time, so the result needs AVX.
+    See https://github.com/EESSI/software-layer/issues/1778
+    """
+    if self.name == 'UCX':
+        cpu_target = get_eessi_envvar('EESSI_SOFTWARE_SUBDIR')
+        generic = cpu_target in (CPU_TARGET_X86_64_GENERIC, CPU_TARGET_AARCH64_GENERIC)
+        if generic or build_option('optarch') == OPTARCH_GENERIC:
+            configopts = self.cfg['configopts']
+            opts = configopts.split()
+            if '--enable-optimizations' in opts:
+                self.cfg['configopts'] = ' '.join(opt for opt in opts if opt != '--enable-optimizations')
+                print_msg("Removed --enable-optimizations from configure options for %s: %s",
+                          self.name, self.cfg['configopts'])
+    else:
+        raise EasyBuildError("UCX-specific hook triggered for non-UCX easyconfig?!")
+
+
 def pre_configure_hook_metabat_filtered_zlib_dep(self, *args, **kwargs):
     """
     Pre-configure hook for MetaBAT:
@@ -2571,6 +2593,7 @@ def post_easyblock_hook(self, *args, **kwargs):
     'ROCm-LLVM': pre_configure_hook_llvm,
     'Score-P': pre_configure_hook_score_p,
     'SymEngine': pre_configure_hook_symengine,
+    'UCX': pre_configure_hook_ucx_generic,
     'Visit': pre_configure_hook_visit,
     'WRF': pre_configure_hook_wrf_aarch64,
     'Zoltan': pre_configure_hook_Zoltan,