Comment # 2 on bug 1087075 from Dr. Werner Fink

Current TeXLive 2017

texlive-20170520-source/texk/lcdf-typetools/lcdf-typetools-src/libefont/t1rw.cc

 inline int
 Type1Reader::eexec(int c)
 {
     unsigned char answer = (unsigned char)(c ^ (_r >> 8));
     _r = (((unsigned char)c + _r) * t1C1 + t1C2) & 0xFFFF;
     return answer;
 }


Next TeXLive 2018 I'm working on

 inline int
 Type1Reader::eexec(int c)
 {
     unsigned char answer = (unsigned char)(c ^ (_r >> 8));
     _r = (((unsigned char)c + _r) * (uint32_t) t1C1 + t1C2) & 0xFFFF;
     return answer;
 }

both with

 enum Type1Defs {
     t1Warmup_ee = 4,
     t1R_ee      = 55665,
     t1R_cs      = 4330,
     t1C1        = 52845,
     t1C2        = 22719
 };

defined in ...texk/lcdf-typetools/lcdf-typetools-src/include/efont/t1cs.hh