Document the CMS_SOA_BYTE_SIZE_TYPE macro

Explain that using a typedef as a template parameter causes the ROOT dicionary generation to fail.
cms-sw · Feb 6, 2024 · 2fe7470 · 2fe7470
1 parent 1f4e998
commit 2fe7470
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/DataFormats/SoATemplate/interface/SoACommon.h b/DataFormats/SoATemplate/interface/SoACommon.h
@@ -52,6 +52,8 @@
 #define _VALUE_TYPE_EIGEN_COLUMN 2
 
 /* The size type need to be "hardcoded" in the template parameters for classes serialized by ROOT */
+/* In practice, using a typedef as a template parameter to the Layout or its ViewTemplateFreeParams member
+ * declaration fails ROOT dictionary generation.  */
 #define CMS_SOA_BYTE_SIZE_TYPE std::size_t
 
 namespace cms::soa {