stdlib build fails even after make clean

Bugzilla Link	1181
Created on	Sep 05, 2016 21:01
Version	svn
OS	Linux
Architecture	PC

Extended Description

This was preceeded by a "make clean" and "./configure":
make[2]: Entering directory '/home/sac/sac/BASE/stdlib'
** Note: modules  Dislin DislinBars DislinQuick DislinCanvas DislinPage DislinPlot3d DislinSystem IplImage CvCapture RGB disabled due to configuration.
  SAC2C   targets/seq/ArrayBasics.done
abort: The module 'ScalarArith'
abort: (/usr/local/libexec/sac2c/1.2.beta-BlackForest-294-7460/tree/host/libScalarArithTree.so) uses an incompatible syntax tree layout. Please update the module and compiler to the most recent version.
compilation failed while Loading SAC program.
targets/seq/GNUmakefile:188: recipe for target 'targets/seq/ArrayBasics.done' failed
make[2]: *** [targets/seq/ArrayBasics.done] Error 1
make[2]: Leaving directory '/home/sac/sac/BASE/stdlib'
GNUmakefile:988: recipe for target 'subtarget-seq-activate-recursive' failed
make[1]: *** [subtarget-seq-activate-recursive] Error 2
make[1]: Leaving directory '/home/sac/sac/BASE/stdlib'
GNUmakefile:841: recipe for target 'install' failed
make: *** [install] Error 2
sac@rattler:~/sac/BASE/stdlib$ 
sac@rattler:~/sac/BASE/stdlib$ ./configure; make -j8; sudo make install
The problem goes away when I do:
  sudo rm -r /usr/local/libexec/sac2c.*
and redo the whole stdlib build.