diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index d19d3229b1..e79775aaf2 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -472,6 +472,9 @@ changes (where available).
   results depending on the number of CPU threads, and occasionally
   wrong colors near the left or right image edge.
 
+- Fixed darktable-cli crashing when `--threads` was set below the
+  number of CPUs.
+
 ## Lua
 
 ### API Version
diff --git a/src/common/darktable.c b/src/common/darktable.c
index c31604f58f..1b07d6f24a 100644
--- a/src/common/darktable.c
+++ b/src/common/darktable.c
@@ -1660,6 +1660,8 @@ int dt_init(int argc,
   }
 
 #ifdef _OPENMP
+  // avoid allocating per-thread buffers for workers excluded by the hard limit
+  darktable.num_openmp_threads = MIN(darktable.num_openmp_threads, omp_get_thread_limit());
   omp_set_num_threads(darktable.num_openmp_threads);
   omp_set_dynamic(FALSE);
 #endif
@@ -2052,6 +2054,13 @@ int dt_init(int argc,
   MagickWandGenesis();
 #endif
 
+#ifdef _OPENMP
+  // GraphicsMagick's init resets the thread count to the number of CPUs,
+  // overriding --threads. dt_alloc_perthread() pools are sized by
+  // dt_get_num_threads(), so a larger team would write past their end.
+  omp_set_num_threads(darktable.num_openmp_threads);
+#endif
+
 #ifdef HAVE_LIBHEIF
   dt_splash_screen_set_progress(_("initializing libheif"));
   heif_init(NULL);