[SCons] Always link to static standard libraries with MinGW

SConstruct

@@ -731,6 +731,8 @@ if env['coverage']:
         print 'Error: coverage testing is only available with GCC.'
         exit(0)
 
+if env['toolchain'] == 'mingw':
+    env.Append(LINKFLAGS=['-static-libgcc', '-static-libstdc++'])
 
 def config_error(message):
     print 'ERROR:', message

src/SConscript

@@ -68,9 +68,6 @@ if localenv['OS'] in ('Darwin', 'Windows', 'Cygwin'):
         localenv.Append(LIBS=localenv['boost_libs'],
                         LIBPATH=localenv['boost_lib_dir'])
 
-if localenv['toolchain'] == 'mingw':
-    localenv.Append(LINKFLAGS=['-static-libgcc', '-static-libstdc++'])
-
 # Build the Cantera shared library using the correct name
 if localenv['layout'] != 'debian':
     # Define the name according to the environmental variable

src/matlab/SConscript

@@ -25,7 +25,6 @@ if localenv['OS'] == 'Windows':
         linkflags.append('/MACHINE:' + machtype)
     elif localenv['CC'] == 'gcc':
         linkflags.append('-Wl,--export-all-symbols')
-        linkflags.extend(['-static-libgcc', '-static-libstdc++'])
 
 elif localenv['OS'] == 'Darwin':
     linklibs = list(env['cantera_libs'])