[tlbuild] [tlbuilders] early report for texlive-20210106 snapshot builds

[Karl Berry]

    Sorry, the icu build systems disallows `make LDFLAGS=-static-libstdc++\'.

I do not get the message compiling current TL sources on CentOS7 (namely
tug.org), using the system compiler. This is using ./Build -C, i.e., the
"native-texlive-build", which translates to

../configure --prefix=/home/texlive/karl/Build/source/inst \
  --datadir=/home/texlive/karl/Build/source/inst \
  --disable-missing \
  --enable-largefile \
  --disable-shared \
  --with-xdvi-x-toolkit=xaw \
  -C

And which ultimately uses
  --enable-cxx-runtime-hack=yes

Checking the resulting xetex binary, libstdc++ is indeed statically
linked. Evidently the "hack" circumvents icu's check way, while your
configure invocation does not. So, maybe try --enable-cxx-runtime-hack?

What the hack actually does is not that complicated: it creates a tiny
shell script CXXLD.sh at the top of the build directory and sets the
standard CXXLD variable to use it. The script then runs g++ to do the
link with various args to accomplish the job, notably
  ... -Wl,-Bstatic -lstdc++ -Wl,-Bdynamic ...
which used to be the standard way to do this.

It is surprising that this approach has not been broken by
compiler/linker "upgrades" somewhere along the way, but evidently it
still works. Yay :). --best, karl.