Fix build errors with multiple Lua libraries

This commit fixes two items: 1. Previously `configure` would search for Lua in known paths, but this could cause the Makefile to use inconsistent header and library paths. For example, if luajit were installed in `/usr/local/include` but lua 5.1 were installed in `/usr/lib/liblua-5.1.so`, the build would attempt to use the luajit headers but link against the lua 5.1 library. To fix this, we switch the order of the search: * First attempt to find an installed LUA library with `pkg-config`. * If we cannot find a library that way, fall back to the known-path scan. This is actually what is already documented in `LUA_POSSIBLE_PATHS`. 2. Add luajit back into `LUA_POSSIBLE_LIB_NAMES`. This was added in 0ac23a4 but quietly reverted in fe98ce4. The changes in the first item also ensure the `CFLAGS` are set properly for luajit. This should fix the issues raised in #1909.

Author: stanhu

build/lua.m4

@@ -6,7 +6,7 @@ AC_DEFUN([CHECK_LUA],
 [dnl
 
 # Possible names for the lua library/package (pkg-config)
-LUA_POSSIBLE_LIB_NAMES="lua54 lua5.4 lua-5.4 lua53 lua5.3 lua-5.3 lua52 lua5.2 lua-5.2 lua51 lua5.1 lua-5.1 lua"
+LUA_POSSIBLE_LIB_NAMES="lua54 lua5.4 lua-5.4 lua53 lua5.3 lua-5.3 lua52 lua5.2 lua-5.2 lua51 lua5.1 lua-5.1 luajit-5.1 luajit lua"
 
 # Possible extensions for the library
 LUA_POSSIBLE_EXTENSIONS="so la sl dll dylib"
@@ -40,41 +40,41 @@ else
  else
  LUA_MANDATORY=no
  fi
- for x in ${LUA_POSSIBLE_PATHS}; do
- CHECK_FOR_LUA_AT(${x})
- if test -n "${LUA_CFLAGS}"; then
- break
- fi
- done
+ # Trying to figure out the version using pkg-config...
+ if test -n "${PKG_CONFIG}"; then
+ LUA_PKG_NAME=""
+ for x in ${LUA_POSSIBLE_LIB_NAMES}; do
+ if ${PKG_CONFIG} --exists ${x}; then
+ LUA_PKG_NAME="$x"
+ LUA_PKG_VERSION="`${PKG_CONFIG} ${LUA_PKG_NAME} --modversion`"
+ break
+ fi
+ done
+ fi
+ if test -n "${LUA_PKG_NAME}"; then
+ # Package was found using the pkg-config scripts
+ LUA_PKG_VERSION="`${PKG_CONFIG} ${LUA_PKG_NAME} --modversion`"
+ LUA_CFLAGS="`${PKG_CONFIG} ${LUA_PKG_NAME} --cflags`"
+ LUA_LDADD="`${PKG_CONFIG} ${LUA_PKG_NAME} --libs-only-l`"
+ LUA_LDFLAGS="`${PKG_CONFIG} ${LUA_PKG_NAME} --libs-only-L --libs-only-other`"
+ LUA_DISPLAY="${LUA_LDADD}, ${LUA_CFLAGS}"
+ case $LUA_PKG_VERSION in
+ (5.4*) LUA_CFLAGS="-DWITH_LUA_5_4 ${LUA_CFLAGS}" ; lua_5_4=1 ;;
+ (5.3*) LUA_CFLAGS="-DWITH_LUA_5_3 ${LUA_CFLAGS}" ; lua_5_3=1 ;;
+ (5.2*) LUA_CFLAGS="-DWITH_LUA_5_2 ${LUA_CFLAGS}" ; lua_5_2=1 ;;
+ (5.1*) LUA_CFLAGS="-DWITH_LUA_5_1 ${LUA_CFLAGS}" ; lua_5_1=1 ;;
+ (2.0*) LUA_CFLAGS="-DWITH_LUA_5_1 ${LUA_CFLAGS}" ; lua_5_1=1 ;;
+ (2.1*) LUA_CFLAGS="-DWITH_LUA_5_1 -DWITH_LUA_JIT_2_1 ${LUA_CFLAGS}" ; lua_5_1=1 ;;
+ esac
+ AC_MSG_NOTICE([LUA pkg-config version: ${LUA_PKG_VERSION}])
+ fi
  if test -z "${LUA_CFLAGS}"; then
- #Trying to figure out the version using pkg-config...
- if test -n "${PKG_CONFIG}"; then
- LUA_PKG_NAME=""
- for x in ${LUA_POSSIBLE_LIB_NAMES}; do
- if ${PKG_CONFIG} --exists ${x}; then
- LUA_PKG_NAME="$x"
- LUA_PKG_VERSION="`${PKG_CONFIG} ${LUA_PKG_NAME} --modversion`"
- break
- fi
- done
- fi
- if test -n "${LUA_PKG_NAME}"; then
- # Package was found using the pkg-config scripts
- LUA_PKG_VERSION="`${PKG_CONFIG} ${LUA_PKG_NAME} --modversion`"
- LUA_CFLAGS="`${PKG_CONFIG} ${LUA_PKG_NAME} --cflags`"
- LUA_LDADD="`${PKG_CONFIG} ${LUA_PKG_NAME} --libs-only-l`"
- LUA_LDFLAGS="`${PKG_CONFIG} ${LUA_PKG_NAME} --libs-only-L --libs-only-other`"
- LUA_DISPLAY="${LUA_LDADD}, ${LUA_CFLAGS}"
- case $LUA_PKG_VERSION in
- (5.1*) LUA_CFLAGS="-DWITH_LUA_5_1 ${LUA_CFLAGS}" ; lua_5_1=1 ;;
- (5.2*) LUA_CFLAGS="-DWITH_LUA_5_2 ${LUA_CFLAGS}" ; lua_5_2=1 ;;
- (5.3*) LUA_CFLAGS="-DWITH_LUA_5_3 ${LUA_CFLAGS}" ; lua_5_3=1 ;;
- (5.4*) LUA_CFLAGS="-DWITH_LUA_5_4 ${LUA_CFLAGS}" ; lua_5_4=1 ;;
- (2.0*) LUA_CFLAGS="-DWITH_LUA_5_1 ${LUA_CFLAGS}" ; lua_5_1=1 ;;
- (2.1*) LUA_CFLAGS="-DWITH_LUA_5_1 -DWITH_LUA_JIT_2_1 ${LUA_CFLAGS}" ; lua_5_1=1 ;;
- esac
- AC_MSG_NOTICE([LUA pkg-config version: ${LUA_PKG_VERSION}])
- fi
+ for x in ${LUA_POSSIBLE_PATHS}; do
+ CHECK_FOR_LUA_AT(${x})
+ if test -n "${LUA_CFLAGS}"; then
+ break
+ fi
+ done
  fi
 fi