Release Notes Form 4.2.1

This release is a minor update from 4.2.0 and mostly contains bug fixes. Below, the most notable changes are listed.

For a full overview of all the changes made, see the full git logs.

Changelog - FORM 4.2.1 (2019-02-01)

Caveats

• The default memory usage has been increased: 400MB -> 2GB for the 64-bit sequential version (689b72d)

Added

Command line options

• -z<TIMEOUT> sets a timelimit in second for the program (689b72d)

• -Z removes the .str file on crash (689b72d)

Setup parameters

• JumpRatio controls whether the lookup of cases in Switch constructs (at runtime) should be done by means of a jumptable or by binary searching, depending on the sparseness of the cases (689b72d)

Preprocessor instructions

• #If
  • sizeof() gives the size of an expression or a $-variable in WORD (f942350)
• #System
  • (undocumented) -e option ignores an error returned by the system() C-library function. The error code is stored in SYSTEMERROR_ (689b72d)
• #TimeoutAfter starts a timer to terminate the current program with a given timeout (689b72d)
• #Write
  • In new %+e and %+E formats, each term starts on a new line (f942350)

Preprocessor variables

• (undocumented) SYSTEMERROR_: see #System -e (689b72d)

Statements

• (undocumented) Added <filename> option in the executable Print statement (f94c1c8)

• Added the ordered option for Set declarations (689b72d)

• Switch construction (at runtime) (689b72d)

  • Switch ... EndSwitch
  • Case
  • Default
  • Break

  They are used for making a switch construction.

Functions

• sizeof_ gives the size of an expression or a $-variable in WORD (f942350)

• topologies_ is used for diagram generation (689b72d)

Improved

• Replaced the obsolete ftime() function with clock_gettime() when the latter is available (#276)
• Improved the algorithms of division and reminder for non-monic multivariate polynomials (#281)
• Removed an inefficiency when many expressions are defined (a261560, 536e778, 7599180; see also #215 (comment))
• Improved the merge sort inside memory based on Timsort (f1b83ae)

Fixed

• Fixed a bug that caused a pattern matching failure for restricted numbers in ex-Polyratfun (#55)
• Fixed crashes in routines for gzip decompression (#95)
• Fixed content_ for polynomials with constant terms (#185)
• Fixed some portability issues (#217, #223)
• Fixed corrupted characters from the prepreocessor calculator when the result is the most negative integer (#219)
• Fixed a crash on accessing the first #factdollar factor of an integer (#222)
• Fixed memory leaks in routines for gzip compression (#248)
• Fixed a memory bug for local $-variables in TFORM (#253)
• Fixed a bug that made gcd_ give wrong results (#258)
• Fixed a bug in the polynomial GCD routine (#260)
• Fixed a wrong "Division by zero" runtime error by mul_(x,0) (#261)
• Fixed a bug that caused wrong results in code optimization (#272)
• Fixed transform,addargs for the case that the result becomes 0 (#277)
• Fixed some bug in LHS patterns with poly(rat)fun and symbols (8e8b0ae)
• Fixed the problem that content_ did not handle functions properly (6eae467)