XCode: error: no member named 'signbit' in the global namespace

Dmitriano

I get the following compiler errors while trying to compile my QT app for iOS:

In file included from /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/random:1637:
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:317:9: error: no member named 'signbit' in the global namespace
using ::signbit;
      ~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:318:9: error: no member named 'fpclassify' in the global namespace
using ::fpclassify;
      ~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:319:9: error: no member named 'isfinite' in the global namespace
using ::isfinite;
      ~~^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/cmath:320:9: error: no member named 'isinf' in the global namespace
using ::isinf;
      ~~^
...
fatal error: too many errors emitted, stopping now [-ferror-limit=]
20 errors generated.

My development environment:

Developer:
 
    Developer Tools:
 
      Version: 11.4.1 (11E503a)
      Location: /Applications/Xcode.app
      Applications:
          Xcode: 11.4.1 (16137)
          Instruments: 11.4.1 (64535.74)
      SDKs:
          iOS:
              13,4: (17E8258)
          iOS Simulator:
              13,4: (17E8258)
          macOS:
              10.15.4: (19E258)
              19,0: 
          tvOS:
              13,4: (17L255)
          tvOS Simulator:
              13,4: (17L255)
          watchOS:
              6,2: (17T255)
          watchOS Simulator:
              6,2: (17T255)

and a clean installation of QT 5.14.2.

What can cause this?