The test are subdivided into several directories. Only the directory ctgen contains more than one program, but it is an exception anyhow. All other directories contain one program, say test.c. It is translated with a file test.cem as result. This test is run, producing output on test.cem.r. The 'expected' output is distributed on files named test.cem.g. The run files in these directories use the makefile in this directory to create the ...cem, ....cem.r files. After creating the ....cem.r files a diff is run between the .r and .g files. The output of these diffs is preceded by the line comparing ....cem Not all differences are caused by errors. Part of the output in the subdirectory ctmargt is a printout of the current environment variables. These will differ per user. The expected output in the directory ctconv is for a compiler that considers char's as unsigned quantaties. The expected output in all directories is generated using 16-bit arithmetic, using 32-bit arithmetic will cause several discrepancies to occur with the expected output in the ...cem.g files. The output of a run with a compiler using 2-bytes int can be found in the file out.std. If any other differences with the expected output occur, the error causing the diffence has to be rooted out by a person with some experience with the kit. Most errors will be caused by the backend programs, so looking at the assembly code generated by such a backend from EM code is a good strategy when looking for a cause. The programs in the directory ctgen are structured somewhat differently. This directory contains a file 'OPS' with a prototype program. This prototype program performs all C arithmetic operations on a few operands. The operands are X, Y, S, Z1, Z2. X, Y and S can be arbitrary expressions, but S is used as a shift count and must be less then 16 (32). Z1 and Z2 must be lvalue's. The name ISTART indicates global declarations and LSTART indicates local declarations. The files ....sed (e.g. test.sed) are used to produce legal C programs from the OPS file, in which the result of all expressions is printed. The programs are run in the way described above.