A fast math parser library

mkdir /data/buildroot/package/muparser
cat > /data/buildroot/package/muparser/Config.in<< 'EOF'
config BR2_PACKAGE_MUPARSER
        bool "muparser"
        help
          A fast math parser library
EOF

cat > /data/buildroot/package/muparser/muparser.mk<< 'EOF'
#############################################################
#
# muparser
#https://github.com/beltoforion/muparser/archive/refs/tags/v2.3.3-1.tar.gz
#############################################################
MUPARSER_VERSION = 2.3.3-1
MUPARSER_SOURCE  = v$(MUPARSER_VERSION).tar.gz
MUPARSER_SITE    = https://github.com/beltoforion/muparser/archive/refs/tags
MUPARSER_INSTALL_STAGING = YES
MUPARSER_INSTALL_TARGET = YES
MUPARSER_SUPPORTS_IN_SOURCE_BUILD = NO 
MUPARSER_CONF_OPTS = -DCMAKE_TOOLCHAIN_FILE=$(HOST_DIR)/share/buildroot/toolchainfile.cmake \
    -DCMAKE_INSTALL_PREFIX=/usr

define MUPARSER_CONFIGURE_CMDS
  if [[ ! -L "$(HOST_DIR)/usr/lib/libpcre.so.3" ]]; then ln -s $(HOST_DIR)/usr/lib/libpcre.so $(HOST_DIR)/usr/lib/libpcre.so.3; fi
  if [[ ! -d $(@D)/buildroot-build ]]; then mkdir $(@D)/buildroot-build; fi
  cd $(@D)/buildroot-build && \
  LDFLAGS="$(LDFLAGS) -pthread -Wl,--as-needed -Wl,--allow-shlib-undefined" cmake "$(@D)/" $(LXQT_CMAKE_CONF_OPTS)
endef

$(eval $(cmake-package))
EOF

sed -i '/menu "Custom packages"/a source "package/muparser/Config.in"' /data/buildroot/package/Config.in