QtWebEngine 5-0.15 does not compile with bison 3.7

The QtWebEngine (Qt-5.15.0) fails to build with bison-3.7 installed on macOS Catalina 10.15.6.
Ninja will stop with the error shown below. The moment the error occurs is not consistent, but it
always happens between [17500-18400/19952] builds of /src/core/debug.

The error occurred in my case because gobject-introspection-1.64.1 now requires bison during build
and my natural response was to just build it.

It should be noted, that the error occurs because of bison, and not because of a parallel
build. I tested it extensively with "make -j1", as well as NINJAOPTS="-j1 -v", in many variations
until I finally pin pointed it down.

The error can also be reproduced with the version provided by Homebrew, assuming bison is
referenced in the LDFLAGS.

While there might be a conflict between bison-3.7 and the nativ provided bison, gobject and MySQL-8.021  build without any problems.

I hope this report will prevent some people from having the same trouble.
All the best,
Marek Schiffer

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/blink/renderer/core/core_generated/precompile_core.h-cc -c gen/third_party/blink/renderer/core/core_generated_jumbo_12.cc -o obj/third_party/blink/renderer/core/core_generated/core_generated_jumbo_12.o
ninja: build stopped: subcommand failed.
make[4]: *** [run_ninja] Error 1
make[3]: *** [debug-all] Error 2
make[2]: *** [sub-gn_run-pro-make_first] Error 2
make[1]: *** [sub-core-make_first] Error 2
make: *** [sub-src-make_first] Error 2