> Reproduced on el7 (CentOS7). Same thing works on el6 (SL6).

Fixed in commit dd937e6. Only enable SSE4.2 crc32c for 64-bit compilation. Still not sure why it worked for 32-bit 
compilation on el6 (SL6).

K.O.


> 
> The error is in the SSE4.2-assembly-accelerated library for computing crc32c checksums. I do 
> not understand this assembly stuff enough to tell what goes wrong.
> 
> In any case, "make linux32" is intended for VME processors that cannot run 64-bit code. These 
> processors also happen to not have the SSE4.2 instructions needed for this code to actually 
> work, so one solution would be to always disable crc32c SSE4.2-assembly-acceleration for the 
> linux32 target.
> 
> Note that the original reported was running "make linux32" with the idea of generating code for 
> the 32-bit ARM processor.
> 
> Here the situation is like this: the required CRC32C instructions are present on 64-bit capable 
> ARM processors (RPi3, etc) and probably work in 32-bit mode, and I found the assembly-
> language crc32c library that uses them. It needs to be added to MIDAS and tested.
> 
> For the older 32-bit-only ARM processors (Cyclone5 FPGA, Rpi2 and older) I do not see any 
> hardware accelerated crc32c implementations, so it uses software computed CRC32 always. 
> (P.S.: I see the current linux kernels have a hardware accelerated library for CRC32C, not sure if 
> it can be imported into MIDAS easily).
> 
> K.O.
> 
> 
> > $ make linux32 ...
> > g++ -m32 -c -g -O2 -Wall -Wno-strict-aliasing -Wuninitialized -Iinclude -
> > Idrivers -Imxml -Imscb/include -DHAVE_FTPLIB -D_LARGEFILE64_SOURCE -DHAVE_ZLIB -
> > DHAVE_MSCB -DHAVE_MONGOOSE6 -DMG_ENABLE_THREADS -DMG_DISABLE_CGI -
> DMG_ENABLE_SSL 
> > -DOS_LINUX -fPIC -Wno-unused-function -o lib/crc32c.o src/crc32c.cxx
> > src/crc32c.cxx: In function ‘uint32_t crc32c_hw(uint32_t, const void*, size_t)’:
> > src/crc32c.cxx:283:66: error: ‘asm’ operand has impossible constraints
> >                      : "r"(next), "0"(crc0), "1"(crc1), "2"(crc2));
> >                                                                   ^
> > src/crc32c.cxx:303:66: error: ‘asm’ operand has impossible constraints
> >                      : "r"(next), "0"(crc0), "1"(crc1), "2"(crc2));
> >                                                                   ^
> > src/crc32c.cxx: In function ‘uint32_t crc32c(uint32_t, const void*, size_t)’:
> > src/crc32c.cxx:348:34: error: PIC register clobbered by ‘%ebx’ in ‘asm’
> >                  : "%ebx", "%edx"); \
> >                                   ^
> > src/crc32c.cxx:362:5: note: in expansion of macro ‘SSE42’
> >      SSE42(sse42);
> >      ^
> > make[1]: *** [lib/crc32c.o] Error 1
> > make[1]: Leaving directory `/home/hh19285/packages/midas'
> > make: *** [linux32] Error 2
> > 
> > Could you please help with getting past this? otherwise we may need to change 
> > our whole experimental setup.
> > 
> > Thank you in advance