libtool problem

[Alice Wonder]

Hello,

Very low bandwidth user, my only connection is using my phone as a 
hotspot which limits me to ~60 Kbits once I use the very low monthly 
allotment (that broadband users usually have used in two days)

I have tried to search web for answers but it is very difficult as many 
sites pull in heavy third party resources.

Okay -

Platform: CentOS 7.5 x86_64 building inside of mock (necessary 
repositories locally mirrored while borrowing bandwidth from library, I 
can keep they rsynced at my slow speed at night so they are current)

Software (audacity) - older version require insecure dependency EPEL 
removed due to its insecurity, building against newer results in GUI 
that doesn't work.

Latest version of audacity requires GCC 4.9 or newer.

So I built a GCC 5.5.0 w/ prefix of /opt/gnu - it's built w/o multilib 
and with just c,c++,objc,objc++ support (I probably only need the first 
two)

With that gcc specified I get this error:


-- terminal output --
gtk/FileDialogPrivate.cpp: In function 'void 
gtk_filedialog_ok_callback(GtkWidget*, FileDialog*)':
gtk/FileDialogPrivate.cpp:103:22: warning: ignoring return value of 'int 
chdir(const char*)', declared with attribute warn_unused_result 
[-Wunused-result]
         chdir(folder);
                      ^
/bin/sh ./libtool    --mode=link g++    -L/opt/gnu/lib64 -L/lib64 
-L/usr/lib64 -o libFileDialog.la -rpath /usr/lib64 
libFileDialog_la-FileDialog.lo gtk/libFileDialog_la-FileDialogPrivate.lo 
   -lgtk-3 -lgdk-3 -latk-1.0 -lgio-2.0 -lpangocairo-1.0 -lgdk_pixbuf-2.0 
-lcairo-gobject -lpango-1.0 -lcairo -lgobject-2.0 -lglib-2.0   -lgtk-3 
-lgdk-3 -latk-1.0 -lgio-2.0 -lpangocairo-1.0 -lgdk_pixbuf-2.0 
-lcairo-gobject -lpango-1.0 -lcairo -lgobject-2.0 -lglib-2.0
libtool: link: unable to infer tagged configuration
libtool: link: specify a tag with `--tag'
make[2]: *** [libFileDialog.la] Error 1
-- /terminal output --

Looking at http://metastatic.org/text/libtool.html from search results, 
I built libtool 2.4.2 (same version CentOS 7 has) rpm from pristine 
source but with a prefix of /opt/gnu and I built it using the gcc 5.5.0 
in /opt/gnu

Still get same error when specifying that libtool to audacity configure.

Looking at audacity, seems they make their own libtool script. I read it 
trying to find where the error might be.

Found the line

-- code --
sys_lib_dlsearch_path_spec="/lib /usr/lib /opt/gnu/lib64 "
-- /code --

Now after configure I try this but still get same error:

-- code --
sed -i -e 's?^sys_lib_dlsearch_path_spec="/lib 
/usr/lib?sys_lib_dlsearch_path_spec="/lib64 /usr/lib64?g' libtool

-- /code --

I know the gcc 5.5.0 build works, I tested that with simple

echo 'int main(){}' > dummy.c

I do however suspect the error is somewhere on my end. Any suggestions?

Full environmental variables I'm passing to audacity configure script:

-- code --
LIBTOOL=/opt/gnu/bin/libtool CC=/opt/gnu/bin/gcc CXX=/opt/gnu/bin/g++ 
CPP=/opt/gnu/bin/cpp LDFLAGS="-L/opt/gnu/lib64" 
CPPFLAGS="-I/opt/gnu/include"
-- /code --


--
You have to be a deviant or exist in dreary boredom. Make no mistake; 
all intellectuals are deviants -- William S. Burroughs