"No support of nested C function" build failure(s) — clang 9.0.1

clang rejects inner functions while gcc accepts them.
void foo() {

     void bar() {

     }

}
PackageVersionSupposed error messageFull log Bug report
bluez 5.50-1profiles/midi/midi.c:79:75: error: function definition is not allowed here Log
eurephia 1.1.0-6eurephiadm.c:203:47: error: function definition is not allowed here Log
growl-for-linux 0.8.5-5balloon.c:160:72: error: function definition is not allowed here Log
gst-plugins-espeak 0.5.0-1espeak.c:211:59: error: function definition is not allowed here Log
kraptor 0.0.20040403+ds-2src/game.c:416:3: error: function definition is not allowed here Log 750370
mandos 1.8.9-2plugin-runner.c:437:66: error: function definition is not allowed here Log 750516
matchbox-panel 0.9.3-10mb-applet-battery.c:182:2: error: function definition is not allowed here Log 750784
netplug 1.2.9.2-3if_info.c:295:37: error: function definition is not allowed here Log 750789
ratpoints 1:2.1.3-1./sturm.c:176:5: error: function definition is not allowed here Log
rsh-redone 85-2rlogin.c:388:30: error: function definition is not allowed here Log 750957
smbc 1.2.2-4smbc.c:316:2: error: function definition is not allowed here Log
v4l-utils 1.18.0-2ir-encode.c:38:2: error: function definition is not allowed here Log
xneur 0.20.0-2text.c:292:25: error: function definition is not allowed here Log 751542

13 errors