From 821e6834d95536af9e12d4978a489f73351e34f6 Mon Sep 17 00:00:00 2001
From: dvdgrgrtt <david.gregoratti@srs.io>
Date: Mon, 4 Oct 2021 15:28:18 +0200
Subject: [PATCH] Fix CMake to work with new CPUs and old GCCs

---
 CMakeLists.txt | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5a2f59324..c6a934fc0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -376,13 +376,16 @@ if(CMAKE_CXX_COMPILER_ID MATCHES "GNU" OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
     find_package(SSE)
   endif (AUTO_DETECT_ISA)
 
+  ADD_C_COMPILER_FLAG_IF_AVAILABLE("-march=${GCC_ARCH}" HAVE_MARCH_${GCC_ARCH})
+  ADD_CXX_COMPILER_FLAG_IF_AVAILABLE("-march=${GCC_ARCH}" HAVE_MARCH_${GCC_ARCH})
+  
   if (HAVE_AVX2)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=${GCC_ARCH} -mfpmath=sse -mavx2 -DLV_HAVE_AVX2 -DLV_HAVE_AVX -DLV_HAVE_SSE")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mfpmath=sse -mavx2 -DLV_HAVE_AVX2 -DLV_HAVE_AVX -DLV_HAVE_SSE")
   else (HAVE_AVX2)
     if(HAVE_AVX)
-      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=${GCC_ARCH} -mfpmath=sse -mavx -DLV_HAVE_AVX -DLV_HAVE_SSE")
+      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mfpmath=sse -mavx -DLV_HAVE_AVX -DLV_HAVE_SSE")
     elseif(HAVE_SSE)
-      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=${GCC_ARCH} -mfpmath=sse -msse4.1 -DLV_HAVE_SSE")
+      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mfpmath=sse -msse4.1 -DLV_HAVE_SSE")
     endif(HAVE_AVX)
   endif (HAVE_AVX2)
 
@@ -432,12 +435,12 @@ if(CMAKE_C_COMPILER_ID MATCHES "GNU" OR CMAKE_C_COMPILER_ID MATCHES "Clang")
     find_package(SSE)
   endif (AUTO_DETECT_ISA)
   if (HAVE_AVX2)
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=${GCC_ARCH} -mfpmath=sse -mavx2 -DLV_HAVE_AVX2 -DLV_HAVE_AVX -DLV_HAVE_SSE")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mfpmath=sse -mavx2 -DLV_HAVE_AVX2 -DLV_HAVE_AVX -DLV_HAVE_SSE")
   else (HAVE_AVX2)
     if(HAVE_AVX)
-      set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=${GCC_ARCH} -mfpmath=sse -mavx -DLV_HAVE_AVX -DLV_HAVE_SSE")
+      set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mfpmath=sse -mavx -DLV_HAVE_AVX -DLV_HAVE_SSE")
     elseif(HAVE_SSE)
-      set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=${GCC_ARCH} -mfpmath=sse -msse4.1 -DLV_HAVE_SSE")
+      set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mfpmath=sse -msse4.1 -DLV_HAVE_SSE")
     endif(HAVE_AVX)
   endif (HAVE_AVX2)