I have been able to reliable reproduce the build race, using make -j > 1.
the following will trigger the build failure.
the proposed patch in message 10 is incomplete.
testbreakcompile.patch
--- a/Makefile.in 2023-07-12 13:55:26.000000000 +0000
+++ b/Makefile.in 2023-07-22 05:00:09.718180145 +0000
@@ -1163,7 +1163,7 @@
@MACOSX_TRUE@wrapped.h wrapdef.h wrapstruct.h wraptmpf.h:wrapawk_macosx
wrapfunc.inp
@MACOSX_TRUE@ awk -f $(srcdir)/wrapawk_macosx < $(srcdir)/wrapfunc.inp
@MACOSX_FALSE@wrapped.h wrapdef.h wrapstruct.h wraptmpf.h:wrapawk wrapfunc.inp
-@MACOSX_FALSE@ awk -f $(srcdir)/wrapawk < $(srcdir)/wrapfunc.inp
+@MACOSX_FALSE@ sleep 100;awk -f $(srcdir)/wrapawk < $(srcdir)/wrapfunc.inp
libfakeroot.lo:libfakeroot.c wrapdef.h wrapstruct.h wraptmpf.h
--- a/Makefile.am 2023-07-22 04:59:30.671246641 +0000
+++ b/Makefile.am 2023-07-22 05:01:52.345546358 +0000
@@ -52,7 +52,7 @@
awk -f $(srcdir)/wrapawk_macosx < $(srcdir)/wrapfunc.inp
else !MACOSX
wrapped.h wrapdef.h wrapstruct.h wraptmpf.h:wrapawk wrapfunc.inp
- awk -f $(srcdir)/wrapawk < $(srcdir)/wrapfunc.inp
+ sleep 100; awk -f $(srcdir)/wrapawk < $(srcdir)/wrapfunc.inp
endif !MACOSX
libfakeroot.lo:libfakeroot.c wrapdef.h wrapstruct.h wraptmpf.h
