[Rd] possible bug in R's configure check for C++11 features

[Kasper Daniel Hansen]

I'm sorry, I'm an idiot for not noticing this. That's what happens when you
have been stuck in configure/make hell for a while.

Best,
Kasper

On Tue, Sep 3, 2019 at 10:54 PM Simon Urbanek <simon.urbanek using r-project.org>
wrote:

> Kasper,
>
> I haven’t checked in depth, so just to clarify: you *are* setting
> CXX11=g++ so it is doing what you asked it to. Since the settings are
> inherited upwards, this implies that you are setting both CXX14 and CXX17
> to g++. So I’m not quite sure I understand your concern.
>
> Cheers,
> Simon
>
>
>
> > On Sep 3, 2019, at 9:02 PM, Kasper Daniel Hansen <
> kasperdanielhansen using gmail.com> wrote:
> >
> > I am trying to compile R under a new setup, and frankly, I have had a lot
> > of problems, but I think the stuff below points to a possible bug in R's
> > (custom) configure checks for C++11/14/17, but not for C++98.
> >
> > This is a report about R from the R-3-6 branch, with a svn checkout from
> > today, revision r77135.
> >
> > In my case the compiler name is x86_64-conda_cos6-linux-gnu-g++, not
> g++. I
> > denote this in my configure call, using the CC variable. A snippet of the
> > full configure is
> >
> > ../${SRCDIR}/configure SHELL='/bin/bash' \
> >   --prefix="${CONDA_PREFIX}/R/${R_VERSION}" \
> >   CC="x86_64-conda_cos6-linux-gnu-gcc" \
> >   CXX="x86_64-conda_cos6-linux-gnu-g++" \
> >   F77="x86_64-conda_cos6-linux-gnu-gfortran" \
> >   FC="$F77" \
> >   CFLAGS="-Wall -mtune=amdfam10 -g -O2 -I${CONDA_PREFIX}/include"\
> >   CXXFLAGS="-Wall -mtune=amdfam10 -g -O2 -I${CONDA_PREFIX}/include" \
> >   F77FLAGS="-Wall -g -O2 -mtune=amdfam10 -I${CONDA_PREFIX}/include" \
> >   CXX11="g++" \
> >   CXX11STD="-std=c++11" \
> >   CXX11FLAGS="-Wall -mtune=amdfam10 -g -O2 -I${CONDA_PREFIX}/include" \
> >   CXX11PICFLAGS="-fPIC" \
> >
> > Where $CONDA_PREFIX is given in my script.
> >
> > The output in config.log is given below. Note that in the test for c++98,
> > it uses the "right" CC, but in the test for c++11 it uses g++. This looks
> > wrong to me:
> >
> > configure:28111: checking whether x86_64-conda_cos6-linux-gnu-g++
> supports
> > C++98 features with -std=gnu++98
> > configure:28130: x86_64-conda_cos6-linux-gnu-g++  -std=gnu++98 -c -Wall
> > -mtune=amdfam10 -g -O2
> > -I/jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/include
> > -fpic -DNDEBUG -D_FORTIFY_SOURCE=2 -O2 conftest.cp
> > p >&5
> > configure:28130: $? = 0
> > configure:28139: result: yes
> > configure:28315: checking whether g++ -std=c++11 supports C++11 features
> > configure:28607: g++ -std=c++11 -c -Wall -mtune=amdfam10 -g -O2
> > -I/jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/include
> > -fPIC -DNDEBUG -D_FORTIFY_SOURCE=2 -O2 conftest.cpp >&5
> > ../R-3.6-src/configure: line 2355: g++: command not found
> > configure:28607: $? = 127
> > configure: failed program was:
> >
> > I have similar issues (wrong CC using when compiling the test program)
> with
> > the test for c++14, whereas the test for c++17 has empty space where the
> CC
> > variable should be?
> >
> > I can fix this issue by adding a soft link in my PATH from g++ to my
> > compiler of choice. In this case configure finishes and reports that I
> have
> > full C++17 capabilities. Weirdly, in the output, note that the C++
> compiler
> > is "wrong" again, despite my configure call:
> >
> >  Source directory:            ../R-3.6-src
> >  Installation directory:
> > /jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/R/3.6
> >
> >  C compiler:                  x86_64-conda_cos6-linux-gnu-gcc  -Wall
> > -mtune=amdfam10 -g -O2
> > -I/jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/include
> >  Fortran fixed-form compiler:
> >
> /jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/bin/x86_64-conda_cos6-linux-gnu-gfortran
> > -fno-optimize-sibling-calls -fopenmp -march=nocona -mtune=haswell
> > -ftree-vectorize -fPIC -fstack-protector-strong -fno-plt -O2
> > -ffunction-sections -pipe
> >
> >  Default C++ compiler:        g++ -std=c++11   -Wall -mtune=amdfam10 -g
> > -O2
> -I/jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/include
> >  C++98 compiler:              x86_64-conda_cos6-linux-gnu-g++
> -std=gnu++98
> > -Wall -mtune=amdfam10 -g -O2
> > -I/jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/include
> >  C++11 compiler:              g++ -std=c++11   -Wall -mtune=amdfam10 -g
> > -O2
> -I/jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/include
> >  C++14 compiler:              g++ -std=gnu++14   -Wall -mtune=amdfam10 -g
> > -O2
> -I/jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/include
> >  C++17 compiler:              g++ -std=gnu++17  -Wall -mtune=amdfam10 -g
> > -O2
> -I/jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/include
> >  Fortran free-form compiler:
> >
> /jhpce/shared/jhpce/core/conda/miniconda3-4.6.14/envs/svnR-3.6/bin/x86_64-conda_cos6-linux-gnu-gfortran
> > -fno-optimize-sibling-calls
> >  Obj-C compiler:
> >
> >
> >
> > --
> > Best,
> > Kasper
> >
> >       [[alternative HTML version deleted]]
> >
> > ______________________________________________
> > R-devel using r-project.org mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-devel
> >
>
>

-- 
Best,
Kasper

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