compilation fails with icc (classic) 2021.4.0

[aepace]

Hi, I'm getting a compilation error using icc 2021.4.0 in a Centos 8 container.

# icc -V
Intel(R) C Intel(R) 64 Compiler Classic for applications running on Intel(R) 64, Version 2021.4.0 Build 20210910_000000
Copyright (C) 1985-2021 Intel Corporation.  All rights reserved.

# gcc --version
gcc (GCC) 8.5.0 20210514 (Red Hat 8.5.0-4)
Copyright (C) 2018 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

The build fails when making all in api with following error:

libtool: compile:  icc -std=gnu99 -DHAVE_CONFIG_H -I. -I.. -I .. -O3 -fPIC -no-gcc -fp-model strict -axCORE-AVX512,CORE-AVX2,AVX,SSE4.2 -I/opt/intel/oneapi/mkl/2021.4.0/include -MT plan-many-r2r.lo -MD -MP -MF .deps/plan-many-r2r.Tpo -c plan-many-r2r.c -o plan-many-r2r.o >/dev/null 2>&1
mv -f .deps/execute-split-dft.Tpo .deps/execute-split-dft.Plo
mv -f .deps/execute-dft-r2c.Tpo .deps/execute-dft-r2c.Plo
version.c(24): error: expected a ";"
  const char X(cc)[] = FFTW_CC;
                       ^

My configure line looks like:

CC=icc CFLAGS='-O3 -fPIC -fp-model strict -axCORE-AVX512,CORE-AVX2,AVX,SSE4.2 -I"${MKLROOT}/include"' LDFLAGS='-L${MKLROOT}/lib/intel64 -lmkl_rt -lpthread -ldl' ./configure  --enable-avx512 --enable-avx2 --enable-avx --enable-shared --enable-sse --enable-sse2  --enable-float --enable-fma

Thanks!

[rdolbeau]

Check the definition of FFTW_CC in your config.h, it should be a string. It's possible the fact you have double-quotes inside your CFLAGS might confuse things. Try removing them, as they are likely not necessary (and not used in your LDFLAGS anyway).

[stevengj]

Probably you want outer double quotes, not outer single quotes:

CFLAGS="-O3 -fPIC -fp-model strict -axCORE-AVX512,CORE-AVX2,AVX,SSE4.2 -I'${MKLROOT}/include'"
LDFLAGS="-L'${MKLROOT}/lib/intel64' -lmkl_rt -lpthread -ldl"

so that ${MKLROOT} gets substituted into the definitions of CFLAGS and LDFLAGS. (If you use outer single quotes, then ${MKLROOT} appears literally in the flags variable.)

[stevengj]

But yes, the literal double quotes in string might be confusing C; this should be fixed by correcting the order of the quotes as I suggested above.

Maybe we need to do some escaping when the #define FFTW_CC is constructed here: https://github.com/FFTW/fftw3/blob/80f5c5cf2a74835d101c38c54001a54de815c956/configure.ac#L747