--- a/SConstruct
+++ b/SConstruct
@@ -89,7 +89,7 @@ Commandline Options:
 build_target = 'all'
 
 # Optimization level
-opt_flags    = ' -g -O3 -DNDEBUG'
+opt_flags    = ' -DNDEBUG'
 
 # Architecture (defaults to build host type)
 compile_arch = ''
@@ -134,26 +134,6 @@ if dbug:
 if gcov:
     opt_flags = opt_flags + ' --coverage -g'
 
-if sysname == 'sunos':
-    compile_arch = ' -mtune=native'
-elif x86:
-    if bits == 32:
-        if machine == 'x86_64':
-            compile_arch = ' -mx32'
-        else:
-            compile_arch = ' -m32 -march=i686'
-            if sysname == 'linux':
-                link_arch = ' -Wl,-melf_i386'
-    else:
-        compile_arch = ' -m64'
-        if sysname == 'linux':
-            link_arch = ' -Wl,-melf_x86_64'
-    link_arch = compile_arch + link_arch
-elif machine == 's390x':
-    compile_arch = ' -mzarch'
-    if bits == 32:
-        compile_arch += ' -m32'
-
 boost      = int(ARGUMENTS.get('boost', 1))
 boost_pool = int(ARGUMENTS.get('boost_pool', 0))
 system_asio= int(ARGUMENTS.get('system_asio', 1))