From ea180cd1ec4cc1501496ef68520c9ecae48376f5 Mon Sep 17 00:00:00 2001
From: Lars Bilke <lars.bilke@ufz.de>
Date: Tue, 21 Nov 2023 09:38:30 +0100
Subject: [PATCH] [cmake] Added --no-as-needed link flag for MKL.

Otherwise required MKL libraries get stripped out (only
libmkl_intel_lp64.so shows up in ldd).
---
 MathLib/CMakeLists.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/MathLib/CMakeLists.txt b/MathLib/CMakeLists.txt
index fbf64644403..80187fb711c 100644
--- a/MathLib/CMakeLists.txt
+++ b/MathLib/CMakeLists.txt
@@ -36,6 +36,10 @@ target_link_libraries(
            Eigen3::Eigen
            $<$<TARGET_EXISTS:OpenMP::OpenMP_CXX>:OpenMP::OpenMP_CXX>
 )
+if(OGS_USE_MKL AND "${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+    # Otherwise required MKL libs get stripped out (don't show up in ldd):
+    target_link_options(MathLib PUBLIC "LINKER:--no-as-needed")
+endif()
 
 if(OGS_USE_LIS)
     target_include_directories(MathLib PUBLIC ${LIS_INCLUDE_DIR})