meson: Always use -fno-strict-aliasing and -fno-strict-overflow

SPA does not respect the C strict aliasing rules at all, so any code
that uses it must be built with -fno-strict-aliasing.  Furthermore,
there is code in SPA that compares pointers that point to different
objects, so -fno-strict-overflow is also needed.

meson.build

@@ -81,6 +81,7 @@ pkgconfig = import('pkgconfig')
 common_flags = [
   '-fvisibility=hidden',
   '-fno-strict-aliasing',
+  '-fno-strict-overflow',
   '-Werror=suggest-attribute=format',
   '-Wsign-compare',
   '-Wpointer-arith',

spa/meson.build

@@ -32,7 +32,7 @@ pkgconfig.generate(filebase : 'lib@0@'.format(spa_name),
   subdirs : spa_name,
   description : 'Simple Plugin API',
   version : spaversion,
-  extra_cflags : '-D_REENTRANT',
+  extra_cflags : ['-D_REENTRANT', '-fno-strict-aliasing', '-fno-strict-overflow'],
   variables : ['plugindir=${libdir}/@0@'.format(spa_name)],
   uninstalled_variables : ['plugindir=${prefix}/spa/plugins'],
 )