[Texmacs-dev] libstdc++ problem

[Kostas Oikonomou]

Perhaps I was not clear in my last post.

Up to a few weeks ago, TeXmacs would build perfectly fine on FreeBSD,
using the system's standard compiler clang/clang++.

When the -stdlib=libstdc++ feature was introduced in configure,
configuration fails:

...
checking whether C++ compiler accepts -stdlib=libstdc++... yes
configure: added libstdc++ in compile flags
checking stdlibc++ linking... no
configure: error: Not able to link with libstdc++
...

I've looked at configure to try to disable this feature, which does not
seem necessary on FreeBSD, but the code is pretty complicated. Any
suggestions would be welcome.

                            Kostas

[Zhaocong Jia]

Hi, I have the same problem, and I think the bug is:

In SVN r10904, or git commit
2359ba694c250f47aec257282fc7737a2511e0fc,
https://github.com/texmacs/texmacs/commit/2359ba694c250f47aec257282fc7737a2511e0fc

it adds option "-stdlib=libstdc++".

But for some clang, it uses compiler-rt instead of libgcc
as the default rtlib and uses libc++ instead of libstdc++
as the default stdlib. So to use libstdc++ you'll have to use
libgcc too, for example:

clang++ -stdlib=libstdc++ -rtlib=libgcc conftest.cpp


I suggest Kostas Oikonomou to post your config.log here.
I suspect there's no GCC on your system.
A quick fix is to remove "libstdc++" part from "configure.in"
and run "autoconf" again.

On my system, the relevent part of config.log is:

configure:4543: added libstdc++ in compile flags
configure:4551: checking stdlibc++ linking
configure:4569: clang++ -o conftest -stdlib=libstdc++ conftest.cpp >&5
/usr/lib/gcc/x86_64-pc-linux-gnu/7.2.0/../../../../x86_64-pc-linux-gnu/bin/ld:
/tmp/conftest-6b28ea.o: undefined reference to
symbol '_Unwind_Resume@@GCC_3.0'
/usr/lib/gcc/x86_64-pc-linux-gnu/7.2.0/libgcc_s.so.1: error adding
symbols: DSO missing from command line
clang-5.0: error: linker command failed with exit code 1 (use -v to
see invocation)
configure:4569: $? = 1
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME ""
| #define PACKAGE_TARNAME ""
| #define PACKAGE_VERSION ""
| #define PACKAGE_STRING ""
| #define PACKAGE_BUGREPORT ""
| #define PACKAGE_URL ""
| #define USE_STACK_TRACE 1
| /* end confdefs.h. */
|
| #include <string>
| #include <iostream>
|
| int
| main ()
| {
|
| std::string t="CompileMe";
| std::cout <<t.size();
| ;
| return 0;
| }
configure:4580: result: no
configure:4582: error: Not able to link with libstdc++