Clean-Up: build.sh -std logic

recipe/build.sh

@@ -1,20 +1,9 @@
 #!/usr/bin/env bash
 
-# find out toolchain C++ standard
-CXX_STANDARD=17
+# avoid side-injection of -std=c++14 flag in some toolchains
 if [[ ${CXXFLAGS} == *"-std=c++14"* ]]; then
     echo "14 -> 17"
     export CXXFLAGS="${CXXFLAGS} -std=c++17"
-    if [[ ! -z ${MACOSX_DEPLOYMENT_TARGET} ]]; then
-        export MACOSX_DEPLOYMENT_TARGET=10.13
-    fi
-elif [[ ${CXXFLAGS} == *"-std=c++17"* ]]; then
-    echo "17"
-    CXX_STANDARD=17
-elif [[ ${CXXFLAGS} == *"-std="* ]]; then
-    echo "ERROR: unknown C++ standard in toolchain!"
-    echo ${CXXFLAGS}
-    exit 1
 fi
 
 # IPO/LTO does only work with certain toolchains
@@ -29,7 +18,6 @@ do
         -S ${SRC_DIR} -B build                \
         -DCMAKE_BUILD_TYPE=RelWithDebInfo     \
         -DCMAKE_VERBOSE_MAKEFILE=ON           \
-        -DCMAKE_CXX_STANDARD=${CXX_STANDARD}  \
         -DCMAKE_INSTALL_LIBDIR=lib            \
         -DCMAKE_INSTALL_PREFIX=${PREFIX}      \
         -DWarpX_openpmd_internal=OFF          \