xref: /freebsd/contrib/bc/NEWS.md (revision 4ba91fa0736bb0672d475b6b56d9e7b06e78ff69)
1# News
2
3## 4.0.0
4
5This is a production release with many fixes, a new command-line option, and a
6big surprise:
7
8* A bug was fixed in `dc`'s `P` command where the item on the stack was *not*
9  popped.
10* Various bugs in the manuals have been fixed.
11* A known bug was fixed where history did not interact well with prompts printed
12  by user code without newlines.
13* A new command-line option, `-R` and `--no-read-prompt` was added to disable
14  just the prompt when using `read()` (`bc`) or `?` (`dc`).
15* And finally, **official support for Windows was added**.
16
17The last item is why this is a major version bump.
18
19Currently, only one set of build options (extra math and prompt enabled, history
20and NLS/locale support disabled, both calculators enabled) is supported on
21Windows. However, both debug and release builds are supported.
22
23In addition, Windows builds are supported for the the library (`bcl`).
24
25For more details about how to build on Windows, see the [README][5] or the
26[build manual][13].
27
28## 3.3.4
29
30This is a production release that fixes a small bug.
31
32The bug was that output was not flushed before a `read()` call, so prompts
33without a newline on the end were not flushed before the `read()` call.
34
35This is such a tiny bug that users only need to upgrade if they are affected.
36
37## 3.3.3
38
39This is a production release with one tweak and fixes for manuals.
40
41The tweak is that `length(0)` returns `1` instead of `0`. In `3.3.1`, I changed
42it so `length(0.x)`, where `x` could be any number of digits, returned the
43`scale`, but `length(0)` still returned `0` because I believe that `0` has `0`
44significant digits.
45
46After request of FreeBSD and considering the arguments of a mathematician,
47compatibility with other `bc`'s, and the expectations of users, I decided to
48make the change.
49
50The fixes for manuals fixed a bug where `--` was rendered as `-`.
51
52## 3.3.2
53
54This is a production release that fixes a divide-by-zero bug in `root()` in the
55[extended math library][16]. All previous versions with `root()` have the bug.
56
57## 3.3.1
58
59This is a production release that fixes a bug.
60
61The bug was in the reporting of number length when the value was 0.
62
63## 3.3.0
64
65This is a production release that changes one behavior and fixes documentation
66bugs.
67
68The changed behavior is the treatment of `-e` and `-f` when given through
69`BC_ENV_ARGS` or `DC_ENV_ARGS`. Now `bc` and `dc` do not exit when those options
70(or their equivalents) are given through those environment variables. However,
71`bc` and `dc` still exit when they or their equivalents are given on the
72command-line.
73
74## 3.2.7
75
76This is a production release that removes a small non-portable shell operation
77in `configure.sh`. This problem was only noticed on OpenBSD, not FreeBSD or
78Linux.
79
80Non-OpenBSD users do ***NOT*** need to upgrade, although NetBSD users may also
81need to upgrade.
82
83## 3.2.6
84
85This is a production release that fixes the build on FreeBSD.
86
87There was a syntax error in `configure.sh` that the Linux shell did not catch,
88and FreeBSD depends on the existence of `tests/all.sh`.
89
90All users that already upgraded to `3.2.5` should update to this release, with
91my apologies for the poor release of `3.2.5`. Other users should skip `3.2.5` in
92favor of this version.
93
94## 3.2.5
95
96This is a production release that fixes several bugs and adds a couple small
97things.
98
99The two most important bugs were bugs that causes `dc` to access memory
100out-of-bounds (crash in debug builds). This was found by upgrading to `afl++`
101from `afl`. Both were caused by a failure to distinguish between the same two
102cases.
103
104Another bug was the failure to put all of the licenses in the `LICENSE.md` file.
105
106Third, some warnings by `scan-build` were found and eliminated. This needed one
107big change: `bc` and `dc` now bail out as fast as possible on fatal errors
108instead of unwinding the stack.
109
110Fourth, the pseudo-random number now attempts to seed itself with `/dev/random`
111if `/dev/urandom` fails.
112
113Finally, this release has a few quality-of-life changes to the build system. The
114usage should not change at all; the only thing that changed was making sure the
115`Makefile.in` was written to rebuild properly when headers changed and to not
116rebuild when not necessary.
117
118## 3.2.4
119
120This is a production release that fixes a warning on `gcc` 6 or older, which
121does not have an attribute that is used.
122
123Users do ***NOT*** need to upgrade if they don't use `gcc` 6 or older.
124
125## 3.2.3
126
127This is a production release that fixes a bug in `gen/strgen.sh`. I recently
128changed `gen/strgen.c`, but I did not change `gen/strgen.sh`.
129
130Users that do not use `gen/strgen.sh` do not need to upgrade.
131
132## 3.2.2
133
134This is a production release that fixes a portability bug in `configure.sh`. The
135bug was using the GNU `find` extension `-wholename`.
136
137## 3.2.1
138
139This is a production release that has one fix for `bcl(3)`. It is technically
140not a bug fix since the behavior is undefined, but the `BclNumber`s that
141`bcl_divmod()` returns will be set to `BCL_ERROR_INVALID_NUM` if there is an
142error. Previously, they were not set.
143
144## 3.2.0
145
146This is a production release that has one bug fix and a major addition.
147
148The bug fix was a missing `auto` variable in the bessel `j()` function in the
149math library.
150
151The major addition is a way to build a version of `bc`'s math code as a library.
152This is done with the `-a` option to `configure.sh`. The API for the library can
153be read in `./manuals/bcl.3.md` or `man bcl` once the library is installed with
154`make install`.
155
156This library was requested by developers before I even finished version 1.0, but
157I could not figure out how to do it until now.
158
159If the library has API breaking changes, the major version of `bc` will be
160incremented.
161
162## 3.1.6
163
164This is a production release that fixes a new warning from Clang 12 for FreeBSD
165and also removes some possible undefined behavior found by UBSan that compilers
166did not seem to take advantage of.
167
168Users do ***NOT*** need to upgrade, if they do not want to.
169
170## 3.1.5
171
172This is a production release that fixes the Chinese locales (which caused `bc`
173to crash) and a crash caused by `bc` executing code when it should not have been
174able to.
175
176***ALL USERS SHOULD UPGRADE.***
177
178## 3.1.4
179
180This is a production release that fixes one bug, changes two behaviors, and
181removes one environment variable.
182
183The bug is like the one in the last release except it applies if files are being
184executed. I also made the fix more general.
185
186The behavior that was changed is that `bc` now exits when given `-e`, `-f`,
187`--expression` or `--file`. However, if the last one of those is `-f-` (using
188`stdin` as the file), `bc` does not exit. If `-f-` exists and is not the last of
189the `-e` and `-f` options (and equivalents), `bc` gives a fatal error and exits.
190
191Next, I removed the `BC_EXPR_EXIT` and `DC_EXPR_EXIT` environment variables
192since their use is not needed with the behavior change.
193
194Finally, I made it so `bc` does not print the header, though the `-q` and
195`--quiet` options were kept for compatibility with GNU `bc`.
196
197## 3.1.3
198
199This is a production release that fixes one minor bug: if `bc` was invoked like
200the following, it would error:
201
202```
203echo "if (1 < 3) 1" | bc
204```
205
206Unless users run into this bug, they do not need to upgrade, but it is suggested
207that they do.
208
209## 3.1.2
210
211This is a production release that adds a way to install *all* locales. Users do
212***NOT*** need to upgrade.
213
214For package maintainers wishing to make use of the change, just pass `-l` to
215`configure.sh`.
216
217## 3.1.1
218
219This is a production release that adds two Spanish locales. Users do ***NOT***
220need to upgrade, unless they want those locales.
221
222## 3.1.0
223
224This is a production release that adjusts one behavior, fixes eight bugs, and
225improves manpages for FreeBSD. Because this release fixes bugs, **users and
226package maintainers should update to this version as soon as possible**.
227
228The behavior that was adjusted was how code from the `-e` and `-f` arguments
229(and equivalents) were executed. They used to be executed as one big chunk, but
230in this release, they are now executed line-by-line.
231
232The first bug fix in how output to `stdout` was handled in `SIGINT`. If a
233`SIGINT` came in, the `stdout` buffer was not correctly flushed. In fact, a
234clean-up function was not getting called. This release fixes that bug.
235
236The second bug is in how `dc` handled input from `stdin`. This affected `bc` as
237well since it was a mishandling of the `stdin` buffer.
238
239The third fixed bug was that `bc` and `dc` could `abort()` (in debug mode) when
240receiving a `SIGTERM`. This one was a race condition with pushing and popping
241items onto and out of vectors.
242
243The fourth bug fixed was that `bc` could leave extra items on the stack and
244thus, not properly clean up some memory. (The memory would still get
245`free()`'ed, but it would not be `free()`'ed when it could have been.)
246
247The next two bugs were bugs in `bc`'s parser that caused crashes when executing
248the resulting code.
249
250The last two bugs were crashes in `dc` that resulted from mishandling of
251strings.
252
253The manpage improvement was done by switching from [ronn][20] to [Pandoc][21] to
254generate manpages. Pandoc generates much cleaner manpages and doesn't leave
255blank lines where they shouldn't be.
256
257## 3.0.3
258
259This is a production release that adds one new feature: specific manpages.
260
261Before this release, `bc` and `dc` only used one manpage each that referred to
262various build options. This release changes it so there is one manpage set per
263relevant build type. Each manual only has information about its particular
264build, and `configure.sh` selects the correct set for install.
265
266## 3.0.2
267
268This is a production release that adds `utf8` locale symlinks and removes an
269unused `auto` variable from the `ceil()` function in the [extended math
270library][16].
271
272Users do ***NOT*** need to update unless they want the locales.
273
274## 3.0.1
275
276This is a production release with two small changes. Users do ***NOT*** need to
277upgrade to this release; however, if they haven't upgraded to `3.0.0` yet, it
278may be worthwhile to upgrade to this release.
279
280The first change is fixing a compiler warning on FreeBSD with strict warnings
281on.
282
283The second change is to make the new implementation of `ceil()` in `lib2.bc`
284much more efficient.
285
286## 3.0.0
287
288*Notes for package maintainers:*
289
290*First, the `2.7.0` release series saw a change in the option parsing. This made
291me change one error message and add a few others. The error message that was
292changed removed one format specifier. This means that `printf()` will seqfault
293on old locale files. Unfortunately, `bc` cannot use any locale files except the
294global ones that are already installed, so it will use the previous ones while
295running tests during install. **If `bc` segfaults while running arg tests when
296updating, it is because the global locale files have not been replaced. Make
297sure to either prevent the test suite from running on update or remove the old
298locale files before updating.** (Removing the locale files can be done with
299`make uninstall` or by running the `locale_uninstall.sh` script.) Once this is
300done, `bc` should install without problems.*
301
302*Second, **the option to build without signal support has been removed**. See
303below for the reasons why.*
304
305This is a production release with some small bug fixes, a few improvements,
306three major bug fixes, and a complete redesign of `bc`'s error and signal
307handling. **Users and package maintainers should update to this version as soon
308as possible.**
309
310The first major bug fix was in how `bc` executed files. Previously, a whole file
311was parsed before it was executed, but if a function is defined *after* code,
312especially if the function definition was actually a redefinition, and the code
313before the definition referred to the previous function, this `bc` would replace
314the function before executing any code. The fix was to make sure that all code
315that existed before a function definition was executed.
316
317The second major bug fix was in `bc`'s `lib2.bc`. The `ceil()` function had a
318bug where a `0` in the decimal place after the truncation position, caused it to
319output the wrong numbers if there was any non-zero digit after.
320
321The third major bug is that when passing parameters to functions, if an
322expression included an array (not an array element) as a parameter, it was
323accepted, when it should have been rejected. It is now correctly rejected.
324
325Beyond that, this `bc` got several improvements that both sped it up, improved
326the handling of signals, and improved the error handling.
327
328First, the requirements for `bc` were pushed back to POSIX 2008. `bc` uses one
329function, `strdup()`, which is not in POSIX 2001, and it is in the X/Open System
330Interfaces group 2001. It is, however, in POSIX 2008, and since POSIX 2008 is
331old enough to be supported anywhere that I care, that should be the requirement.
332
333Second, the BcVm global variable was put into `bss`. This actually slightly
334reduces the size of the executable from a massive code shrink, and it will stop
335`bc` from allocating a large set of memory when `bc` starts.
336
337Third, the default Karatsuba length was updated from 64 to 32 after making the
338optimization changes below, since 32 is going to be better than 64 after the
339changes.
340
341Fourth, Spanish translations were added.
342
343Fifth, the interpreter received a speedup to make performance on non-math-heavy
344scripts more competitive with GNU `bc`. While improvements did, in fact, get it
345much closer (see the [benchmarks][19]), it isn't quite there.
346
347There were several things done to speed up the interpreter:
348
349First, several small inefficiencies were removed. These inefficiencies included
350calling the function `bc_vec_pop(v)` twice instead of calling
351`bc_vec_npop(v, 2)`. They also included an extra function call for checking the
352size of the stack and checking the size of the stack more than once on several
353operations.
354
355Second, since the current `bc` function is the one that stores constants and
356strings, the program caches pointers to the current function's vectors of
357constants and strings to prevent needing to grab the current function in order
358to grab a constant or a string.
359
360Third, `bc` tries to reuse `BcNum`'s (the internal representation of
361arbitary-precision numbers). If a `BcNum` has the default capacity of
362`BC_NUM_DEF_SIZE` (32 on 64-bit and 16 on 32-bit) when it is freed, it is added
363to a list of available `BcNum`'s. And then, when a `BcNum` is allocated with a
364capacity of `BC_NUM_DEF_SIZE` and any `BcNum`'s exist on the list of reusable
365ones, one of those ones is grabbed instead.
366
367In order to support these changes, the `BC_NUM_DEF_SIZE` was changed. It used to
368be 16 bytes on all systems, but it was changed to more closely align with the
369minimum allocation size on Linux, which is either 32 bytes (64-bit musl), 24
370bytes (64-bit glibc), 16 bytes (32-bit musl), or 12 bytes (32-bit glibc). Since
371these are the minimum allocation sizes, these are the sizes that would be
372allocated anyway, making it worth it to just use the whole space, so the value
373of `BC_NUM_DEF_SIZE` on 64-bit systems was changed to 32 bytes.
374
375On top of that, at least on 64-bit, `BC_NUM_DEF_SIZE` supports numbers with
376either 72 integer digits or 45 integer digits and 27 fractional digits. This
377should be more than enough for most cases since `bc`'s default `scale` values
378are 0 or 20, meaning that, by default, it has at most 20 fractional digits. And
37945 integer digits are *a lot*; it's enough to calculate the amount of mass in
380the Milky Way galaxy in kilograms. Also, 72 digits is enough to calculate the
381diameter of the universe in Planck lengths.
382
383(For 32-bit, these numbers are either 32 integer digits or 12 integer digits and
38420 fractional digits. These are also quite big, and going much bigger on a
38532-bit system seems a little pointless since 12 digits in just under a trillion
386and 20 fractional digits is still enough for about any use since `10^-20` light
387years is just under a millimeter.)
388
389All of this together means that for ordinary uses, and even uses in scientific
390work, the default number size will be all that is needed, which means that
391nearly all, if not all, numbers will be reused, relieving pressure on the system
392allocator.
393
394I did several experiments to find the changes that had the most impact,
395especially with regard to reusing `BcNum`'s. One was putting `BcNum`'s into
396buckets according to their capacity in powers of 2 up to 512. That performed
397worse than `bc` did in `2.7.2`. Another was putting any `BcNum` on the reuse
398list that had a capacity of `BC_NUM_DEF_SIZE * 2` and reusing them for `BcNum`'s
399that requested `BC_NUM_DEF_SIZE`. This did reduce the amount of time spent, but
400it also spent a lot of time in the system allocator for an unknown reason. (When
401using `strace`, a bunch more `brk` calls showed up.) Just reusing `BcNum`'s that
402had exactly `BC_NUM_DEF_SIZE` capacity spent the smallest amount of time in both
403user and system time. This makes sense, especially with the changes to make
404`BC_NUM_DEF_SIZE` bigger on 64-bit systems, since the vast majority of numbers
405will only ever use numbers with a size less than or equal to `BC_NUM_DEF_SIZE`.
406
407Last of all, `bc`'s signal handling underwent a complete redesign. (This is the
408reason that this version is `3.0.0` and not `2.8.0`.) The change was to move
409from a polling approach to signal handling to an interrupt-based approach.
410
411Previously, every single loop condition had a check for signals. I suspect that
412this could be expensive when in tight loops.
413
414Now, the signal handler just uses `longjmp()` (actually `siglongjmp()`) to start
415an unwinding of the stack until it is stopped or the stack is unwound to
416`main()`, which just returns. If `bc` is currently executing code that cannot be
417safely interrupted (according to POSIX), then signals are "locked." The signal
418handler checks if the lock is taken, and if it is, it just sets the status to
419indicate that a signal arrived. Later, when the signal lock is released, the
420status is checked to see if a signal came in. If so, the stack unwinding starts.
421
422This design eliminates polling in favor of maintaining a stack of `jmp_buf`'s.
423This has its own performance implications, but it gives better interaction. And
424the cost of pushing and popping a `jmp_buf` in a function is paid at most twice.
425Most functions do not pay that price, and most of the rest only pay it once.
426(There are only some 3 functions in `bc` that push and pop a `jmp_buf` twice.)
427
428As a side effect of this change, I had to eliminate the use of `stdio.h` in `bc`
429because `stdio` does not play nice with signals and `longjmp()`. I implemented
430custom I/O buffer code that takes a fraction of the size. This means that static
431builds will be smaller, but non-static builds will be bigger, though they will
432have less linking time.
433
434This change is also good because my history implementation was already bypassing
435`stdio` for good reasons, and unifying the architecture was a win.
436
437Another reason for this change is that my `bc` should *always* behave correctly
438in the presence of signals like `SIGINT`, `SIGTERM`, and `SIGQUIT`. With the
439addition of my own I/O buffering, I needed to also make sure that the buffers
440were correctly flushed even when such signals happened.
441
442For this reason, I **removed the option to build without signal support**.
443
444As a nice side effect of this change, the error handling code could be changed
445to take advantage of the stack unwinding that signals used. This means that
446signals and error handling use the same code paths, which means that the stack
447unwinding is well-tested. (Errors are tested heavily in the test suite.)
448
449It also means that functions do not need to return a status code that
450***every*** caller needs to check. This eliminated over 100 branches that simply
451checked return codes and then passed that return code up the stack if necessary.
452The code bloat savings from this is at least 1700 bytes on `x86_64`, *before*
453taking into account the extra code from removing `stdio.h`.
454
455## 2.7.2
456
457This is a production release with one major bug fix.
458
459The `length()` built-in function can take either a number or an array. If it
460takes an array, it returns the length of the array. Arrays can be passed by
461reference. The bug is that the `length()` function would not properly
462dereference arrays that were references. This is a bug that affects all users.
463
464**ALL USERS SHOULD UPDATE `bc`**.
465
466## 2.7.1
467
468This is a production release with fixes for new locales and fixes for compiler
469warnings on FreeBSD.
470
471## 2.7.0
472
473This is a production release with a bug fix for Linux, new translations, and new
474features.
475
476Bug fixes:
477
478* Option parsing in `BC_ENV_ARGS` was broken on Linux in 2.6.1 because `glibc`'s
479  `getopt_long()` is broken. To get around that, and to support long options on
480  every platform, an adapted version of [`optparse`][17] was added. Now, `bc`
481  does not even use `getopt()`.
482* Parsing `BC_ENV_ARGS` with quotes now works. It isn't the smartest, but it
483  does the job if there are spaces in file names.
484
485The following new languages are supported:
486
487* Dutch
488* Polish
489* Russian
490* Japanes
491* Simplified Chinese
492
493All of these translations were generated using [DeepL][18], so improvements are
494welcome.
495
496There is only one new feature: **`bc` now has a built-in pseudo-random number
497generator** (PRNG).
498
499The PRNG is seeded, making it useful for applications where
500`/dev/urandom` does not work because output needs to be reproducible. However,
501it also uses `/dev/urandom` to seed itself by default, so it will start with a
502good seed by default.
503
504It also outputs 32 bits on 32-bit platforms and 64 bits on 64-bit platforms, far
505better than the 15 bits of C's `rand()` and `bash`'s `$RANDOM`.
506
507In addition, the PRNG can take a bound, and when it gets a bound, it
508automatically adjusts to remove bias. It can also generate numbers of arbitrary
509size. (As of the time of release, the largest pseudo-random number generated by
510this `bc` was generated with a bound of `2^(2^20)`.)
511
512***IMPORTANT: read the [`bc` manual][9] and the [`dc` manual][10] to find out
513exactly what guarantees the PRNG provides. The underlying implementation is not
514guaranteed to stay the same, but the guarantees that it provides are guaranteed
515to stay the same regardless of the implementation.***
516
517On top of that, four functions were added to `bc`'s [extended math library][16]
518to make using the PRNG easier:
519
520* `frand(p)`: Generates a number between `[0,1)` to `p` decimal places.
521* `ifrand(i, p)`: Generates an integer with bound `i` and adds it to `frand(p)`.
522* `srand(x)`: Randomizes the sign of `x`. In other words, it flips the sign of
523  `x` with probability `0.5`.
524* `brand()`: Returns a random boolean value (either `0` or `1`).
525
526## 2.6.1
527
528This is a production release with a bug fix for FreeBSD.
529
530The bug was that when `bc` was built without long options, it would give a fatal
531error on every run. This was caused by a mishandling of `optind`.
532
533## 2.6.0
534
535This release is a production release ***with no bugfixes***. If you do not want
536to upgrade, you don't have to.
537
538No source code changed; the only thing that changed was `lib2.bc`.
539
540This release adds one function to the [extended math library][16]: `p(x, y)`,
541which calculates `x` to the power of `y`, whether or not `y` is an integer. (The
542`^` operator can only accept integer powers.)
543
544This release also includes a couple of small tweaks to the [extended math
545library][16], mostly to fix returning numbers with too high of `scale`.
546
547## 2.5.3
548
549This release is a production release which addresses inconsistencies in the
550Portuguese locales. No `bc` code was changed.
551
552The issues were that the ISO files used different naming, and also that the
553files that should have been symlinks were not. I did not catch that because
554GitHub rendered them the exact same way.
555
556## 2.5.2
557
558This release is a production release.
559
560No code was changed, but the build system was changed to allow `CFLAGS` to be
561given to `CC`, like this:
562
563```
564CC="gcc -O3 -march=native" ./configure.sh
565```
566
567If this happens, the flags are automatically put into `CFLAGS`, and the compiler
568is set appropriately. In the example above this means that `CC` will be "gcc"
569and `CFLAGS` will be "-O3 -march=native".
570
571This behavior was added to conform to GNU autotools practices.
572
573## 2.5.1
574
575This is a production release which addresses portability concerns discovered
576in the `bc` build system. No `bc` code was changed.
577
578* Support for Solaris SPARC and AIX were added.
579* Minor documentations edits were performed.
580* An option for `configure.sh` was added to disable long options if
581  `getopt_long()` is missing.
582
583## 2.5.0
584
585This is a production release with new translations. No code changed.
586
587The translations were contributed by [bugcrazy][15], and they are for
588Portuguese, both Portugal and Brazil locales.
589
590## 2.4.0
591
592This is a production release primarily aimed at improving `dc`.
593
594* A couple of copy and paste errors in the [`dc` manual][10] were fixed.
595* `dc` startup was optimized by making sure it didn't have to set up `bc`-only
596  things.
597* The `bc` `&&` and `||` operators were made available to `dc` through the `M`
598  and `m` commands, respectively.
599* `dc` macros were changed to be tail call-optimized.
600
601The last item, tail call optimization, means that if the last thing in a macro
602is a call to another macro, then the old macro is popped before executing the
603new macro. This change was made to stop `dc` from consuming more and more memory
604as macros are executed in a loop.
605
606The `q` and `Q` commands still respect the "hidden" macros by way of recording
607how many macros were removed by tail call optimization.
608
609## 2.3.2
610
611This is a production release meant to fix warnings in the Gentoo `ebuild` by
612making it possible to disable binary stripping. Other users do *not* need to
613upgrade.
614
615## 2.3.1
616
617This is a production release. It fixes a bug that caused `-1000000000 < -1` to
618return `0`. This only happened with negative numbers and only if the value on
619the left was more negative by a certain amount. That said, this bug *is* a bad
620bug, and needs to be fixed.
621
622**ALL USERS SHOULD UPDATE `bc`**.
623
624## 2.3.0
625
626This is a production release with changes to the build system.
627
628## 2.2.0
629
630This release is a production release. It only has new features and performance
631improvements.
632
6331.	The performance of `sqrt(x)` was improved.
6342.	The new function `root(x, n)` was added to the extended math library to
635	calculate `n`th roots.
6363.	The new function `cbrt(x)` was added to the extended math library to
637	calculate cube roots.
638
639## 2.1.3
640
641This is a non-critical release; it just changes the build system, and in
642non-breaking ways:
643
6441.	Linked locale files were changed to link to their sources with a relative
645	link.
6462.	A bug in `configure.sh` that caused long option parsing to fail under `bash`
647	was fixed.
648
649## 2.1.2
650
651This release is not a critical release.
652
6531.	A few codes were added to history.
6542.	Multiplication was optimized a bit more.
6553.	Addition and subtraction were both optimized a bit more.
656
657## 2.1.1
658
659This release contains a fix for the test suite made for Linux from Scratch: now
660the test suite prints `pass` when a test is passed.
661
662Other than that, there is no change in this release, so distros and other users
663do not need to upgrade.
664
665## 2.1.0
666
667This release is a production release.
668
669The following bugs were fixed:
670
6711.	A `dc` bug that caused stack mishandling was fixed.
6722.	A warning on OpenBSD was fixed.
6733.	Bugs in `ctrl+arrow` operations in history were fixed.
6744.	The ability to paste multiple lines in history was added.
6755.	A `bc` bug, mishandling of array arguments to functions, was fixed.
6766.	A crash caused by freeing the wrong pointer was fixed.
6777.	A `dc` bug where strings, in a rare case, were mishandled in parsing was
678	fixed.
679
680In addition, the following changes were made:
681
6821.	Division was slightly optimized.
6832.	An option was added to the build to disable printing of prompts.
6843.	The special case of empty arguments is now handled. This is to prevent
685	errors in scripts that end up passing empty arguments.
6864.	A harmless bug was fixed. This bug was that, with the pop instructions
687	(mostly) removed (see below), `bc` would leave extra values on its stack for
688	`void` functions and in a few other cases. These extra items would not
689	affect anything put on the stack and would not cause any sort of crash or
690	even buggy behavior, but they would cause `bc` to take more memory than it
691	needed.
692
693On top of the above changes, the following optimizations were added:
694
6951.	The need for pop instructions in `bc` was removed.
6962.	Extra tests on every iteration of the interpreter loop were removed.
6973.	Updating function and code pointers on every iteration of the interpreter
698	loop was changed to only updating them when necessary.
6994.	Extra assignments to pointers were removed.
700
701Altogether, these changes sped up the interpreter by around 2x.
702
703***NOTE***: This is the last release with new features because this `bc` is now
704considered complete. From now on, only bug fixes and new translations will be
705added to this `bc`.
706
707## 2.0.3
708
709This is a production, bug-fix release.
710
711Two bugs were fixed in this release:
712
7131.	A rare and subtle signal handling bug was fixed.
7142.	A misbehavior on `0` to a negative power was fixed.
715
716The last bug bears some mentioning.
717
718When I originally wrote power, I did not thoroughly check its error cases;
719instead, I had it check if the first number was `0` and then if so, just return
720`0`. However, `0` to a negative power means that `1` will be divided by `0`,
721which is an error.
722
723I caught this, but only after I stopped being cocky. You see, sometime later, I
724had noticed that GNU `bc` returned an error, correctly, but I thought it was
725wrong simply because that's not what my `bc` did. I saw it again later and had a
726double take. I checked for real, finally, and found out that my `bc` was wrong
727all along.
728
729That was bad on me. But the bug was easy to fix, so it is fixed now.
730
731There are two other things in this release:
732
7331.	Subtraction was optimized by [Stefan Eßer][14].
7342.	Division was also optimized, also by Stefan Eßer.
735
736## 2.0.2
737
738This release contains a fix for a possible overflow in the signal handling. I
739would be surprised if any users ran into it because it would only happen after 2
740billion (`2^31-1`) `SIGINT`'s, but I saw it and had to fix it.
741
742## 2.0.1
743
744This release contains very few things that will apply to any users.
745
7461.	A slight bug in `dc`'s interactive mode was fixed.
7472.	A bug in the test suite that was only triggered on NetBSD was fixed.
7483.	**The `-P`/`--no-prompt` option** was added for users that do not want a
749	prompt.
7504.	A `make check` target was added as an alias for `make test`.
7515.	`dc` got its own read prompt: `?> `.
752
753## 2.0.0
754
755This release is a production release.
756
757This release is also a little different from previous releases. From here on
758out, I do not plan on adding any more features to this `bc`; I believe that it
759is complete. However, there may be bug fix releases in the future, if I or any
760others manage to find bugs.
761
762This release has only a few new features:
763
7641.	`atan2(y, x)` was added to the extended math library as both `a2(y, x)` and
765	`atan2(y, x)`.
7662.	Locales were fixed.
7673.	A **POSIX shell-compatible script was added as an alternative to compiling
768	`gen/strgen.c`** on a host machine. More details about making the choice
769	between the two can be found by running `./configure.sh --help` or reading
770	the [build manual][13].
7714.	Multiplication was optimized by using **diagonal multiplication**, rather
772	than straight brute force.
7735.	The `locale_install.sh` script was fixed.
7746.	`dc` was given the ability to **use the environment variable
775	`DC_ENV_ARGS`**.
7767.	`dc` was also given the ability to **use the `-i` or `--interactive`**
777	options.
7788.	Printing the prompt was fixed so that it did not print when it shouldn't.
7799.	Signal handling was fixed.
78010.	**Handling of `SIGTERM` and `SIGQUIT`** was fixed.
78111.	The **built-in functions `maxibase()`, `maxobase()`, and `maxscale()`** (the
782	commands `T`, `U`, `V` in `dc`, respectively) were added to allow scripts to
783	query for the max allowable values of those globals.
78412.	Some incompatibilities with POSIX were fixed.
785
786In addition, this release is `2.0.0` for a big reason: the internal format for
787numbers changed. They used to be a `char` array. Now, they are an array of
788larger integers, packing more decimal digits into each integer. This has
789delivered ***HUGE*** performance improvements, especially for multiplication,
790division, and power.
791
792This `bc` should now be the fastest `bc` available, but I may be wrong.
793
794## 1.2.8
795
796This release contains a fix for a harmless bug (it is harmless in that it still
797works, but it just copies extra data) in the [`locale_install.sh`][12] script.
798
799## 1.2.7
800
801This version contains fixes for the build on Arch Linux.
802
803## 1.2.6
804
805This release removes the use of `local` in shell scripts because it's not POSIX
806shell-compatible, and also updates a man page that should have been updated a
807long time ago but was missed.
808
809## 1.2.5
810
811This release contains some missing locale `*.msg` files.
812
813## 1.2.4
814
815This release contains a few bug fixes and new French translations.
816
817## 1.2.3
818
819This release contains a fix for a bug: use of uninitialized data. Such data was
820only used when outputting an error message, but I am striving for perfection. As
821Michelangelo said, "Trifles make perfection, and perfection is no trifle."
822
823## 1.2.2
824
825This release contains fixes for OpenBSD.
826
827## 1.2.1
828
829This release contains bug fixes for some rare bugs.
830
831## 1.2.0
832
833This is a production release.
834
835There have been several changes since `1.1.0`:
836
8371.	The build system had some changes.
8382.	Locale support has been added. (Patches welcome for translations.)
8393.	**The ability to turn `ibase`, `obase`, and `scale` into stacks** was added
840	with the `-g` command-line option. (See the [`bc` manual][9] for more
841	details.)
8424.	Support for compiling on Mac OSX out of the box was added.
8435.	The extended math library got `t(x)`, `ceil(x)`, and some aliases.
8446.	The extended math library also got `r2d(x)` (for converting from radians to
845	degrees) and `d2r(x)` (for converting from degrees to radians). This is to
846	allow using degrees with the standard library.
8477.	Both calculators now accept numbers in **scientific notation**. See the
848	[`bc` manual][9] and the [`dc` manual][10] for details.
8498.	Both calculators can **output in either scientific or engineering
850	notation**. See the [`bc` manual][9] and the [`dc` manual][10] for details.
8519.	Some inefficiencies were removed.
85210.	Some bugs were fixed.
85311.	Some bugs in the extended library were fixed.
85412.	Some defects from [Coverity Scan][11] were fixed.
855
856## 1.1.4
857
858This release contains a fix to the build system that allows it to build on older
859versions of `glibc`.
860
861## 1.1.3
862
863This release contains a fix for a bug in the test suite where `bc` tests and
864`dc` tests could not be run in parallel.
865
866## 1.1.2
867
868This release has a fix for a history bug; the down arrow did not work.
869
870## 1.1.1
871
872This release fixes a bug in the `1.1.0` build system. The source is exactly the
873same.
874
875The bug that was fixed was a failure to install if no `EXECSUFFIX` was used.
876
877## 1.1.0
878
879This is a production release. However, many new features were added since `1.0`.
880
8811.	**The build system has been changed** to use a custom, POSIX
882	shell-compatible configure script ([`configure.sh`][6]) to generate a POSIX
883	make-compatible `Makefile`, which means that `bc` and `dc` now build out of
884	the box on any POSIX-compatible system.
8852.	Out-of-memory and output errors now cause the `bc` to report the error,
886	clean up, and die, rather than just reporting and trying to continue.
8873.	**Strings and constants are now garbage collected** when possible.
8884.	Signal handling and checking has been made more simple and more thorough.
8895.	`BcGlobals` was refactored into `BcVm` and `BcVm` was made global. Some
890	procedure names were changed to reflect its difference to everything else.
8916.	Addition got a speed improvement.
8927.	Some common code for addition and multiplication was refactored into its own
893	procedure.
8948.	A bug was removed where `dc` could have been selected, but the internal
895	`#define` that returned `true` for a query about `dc` would not have
896	returned `true`.
8979.	Useless calls to `bc_num_zero()` were removed.
89810.	**History support was added.** The history support is based off of a
899	[UTF-8 aware fork][7] of [`linenoise`][8], which has been customized with
900	`bc`'s own data structures and signal handling.
90111.	Generating C source from the math library now removes tabs from the library,
902	shrinking the size of the executable.
90312.	The math library was shrunk.
90413.	Error handling and reporting was improved.
90514.	Reallocations were reduced by giving access to the request size for each
906	operation.
90715.	**`abs()` (`b` command for `dc`) was added as a builtin.**
90816.	Both calculators were tested on FreeBSD.
90917.	Many obscure parse bugs were fixed.
91018.	Markdown and man page manuals were added, and the man pages are installed by
911	`make install`.
91219.	Executable size was reduced, though the added features probably made the
913	executable end up bigger.
91420.	**GNU-style array references were added as a supported feature.**
91521.	Allocations were reduced.
91622.	**New operators were added**: `$` (`$` for `dc`), `@` (`@` for `dc`), `@=`,
917	`<<` (`H` for `dc`), `<<=`, `>>` (`h` for `dc`), and `>>=`. See the
918	[`bc` manual][9] and the [`dc` manual][10] for more details.
91923.	**An extended math library was added.** This library contains code that
920	makes it so I can replace my desktop calculator with this `bc`. See the
921	[`bc` manual][3] for more details.
92224.	Support for all capital letters as numbers was added.
92325.	**Support for GNU-style void functions was added.**
92426.	A bug fix for improper handling of function parameters was added.
92527.	Precedence for the or (`||`) operator was changed to match GNU `bc`.
92628.	`dc` was given an explicit negation command.
92729.	`dc` was changed to be able to handle strings in arrays.
928
929## 1.1 Release Candidate 3
930
931This release is the eighth release candidate for 1.1, though it is the third
932release candidate meant as a general release candidate. The new code has not
933been tested as thoroughly as it should for release.
934
935## 1.1 Release Candidate 2
936
937This release is the seventh release candidate for 1.1, though it is the second
938release candidate meant as a general release candidate. The new code has not
939been tested as thoroughly as it should for release.
940
941## 1.1 FreeBSD Beta 5
942
943This release is the sixth release candidate for 1.1, though it is the fifth
944release candidate meant specifically to test if `bc` works on FreeBSD. The new
945code has not been tested as thoroughly as it should for release.
946
947## 1.1 FreeBSD Beta 4
948
949This release is the fifth release candidate for 1.1, though it is the fourth
950release candidate meant specifically to test if `bc` works on FreeBSD. The new
951code has not been tested as thoroughly as it should for release.
952
953## 1.1 FreeBSD Beta 3
954
955This release is the fourth release candidate for 1.1, though it is the third
956release candidate meant specifically to test if `bc` works on FreeBSD. The new
957code has not been tested as thoroughly as it should for release.
958
959## 1.1 FreeBSD Beta 2
960
961This release is the third release candidate for 1.1, though it is the second
962release candidate meant specifically to test if `bc` works on FreeBSD. The new
963code has not been tested as thoroughly as it should for release.
964
965## 1.1 FreeBSD Beta 1
966
967This release is the second release candidate for 1.1, though it is meant
968specifically to test if `bc` works on FreeBSD. The new code has not been tested as
969thoroughly as it should for release.
970
971## 1.1 Release Candidate 1
972
973This is the first release candidate for 1.1. The new code has not been tested as
974thoroughly as it should for release.
975
976## 1.0
977
978This is the first non-beta release. `bc` is ready for production use.
979
980As such, a lot has changed since 0.5.
981
9821.	`dc` has been added. It has been tested even more thoroughly than `bc` was
983	for `0.5`. It does not have the `!` command, and for security reasons, it
984	never will, so it is complete.
9852.	`bc` has been more thoroughly tested. An entire section of the test suite
986	(for both programs) has been added to test for errors.
9873.	A prompt (`>>> `) has been added for interactive mode, making it easier to
988	see inputs and outputs.
9894.	Interrupt handling has been improved, including elimination of race
990	conditions (as much as possible).
9915.	MinGW and [Windows Subsystem for Linux][1] support has been added (see
992	[xstatic][2] for binaries).
9936.	Memory leaks and errors have been eliminated (as far as ASan and Valgrind
994	can tell).
9957.	Crashes have been eliminated (as far as [afl][3] can tell).
9968.	Karatsuba multiplication was added (and thoroughly) tested, speeding up
997	multiplication and power by orders of magnitude.
9989.	Performance was further enhanced by using a "divmod" function to reduce
999	redundant divisions and by removing superfluous `memset()` calls.
100010.	To switch between Karatsuba and `O(n^2)` multiplication, the config variable
1001	`BC_NUM_KARATSUBA_LEN` was added. It is set to a sane default, but the
1002	optimal number can be found with [`karatsuba.py`][4] (requires Python 3)
1003	and then configured through `make`.
100411.	The random math test generator script was changed to Python 3 and improved.
1005	`bc` and `dc` have together been run through 30+ million random tests.
100612.	All known math bugs have been fixed, including out of control memory
1007	allocations in `sine` and `cosine` (that was actually a parse bug), certain
1008	cases of infinite loop on square root, and slight inaccuracies (as much as
1009	possible; see the [README][5]) in transcendental functions.
101013.	Parsing has been fixed as much as possible.
101114.	Test coverage was improved to 94.8%. The only paths not covered are ones
1012	that happen when `malloc()` or `realloc()` fails.
101315.	An extension to get the length of an array was added.
101416.	The boolean not (`!`) had its precedence change to match negation.
101517.	Data input was hardened.
101618.	`bc` was made fully compliant with POSIX when the `-s` flag is used or
1017	`POSIXLY_CORRECT` is defined.
101819.	Error handling was improved.
101920.	`bc` now checks that files it is given are not directories.
1020
1021## 1.0 Release Candidate 7
1022
1023This is the seventh release candidate for 1.0. It fixes a few bugs in 1.0
1024Release Candidate 6.
1025
1026## 1.0 Release Candidate 6
1027
1028This is the sixth release candidate for 1.0. It fixes a few bugs in 1.0 Release
1029Candidate 5.
1030
1031## 1.0 Release Candidate 5
1032
1033This is the fifth release candidate for 1.0. It fixes a few bugs in 1.0 Release
1034Candidate 4.
1035
1036## 1.0 Release Candidate 4
1037
1038This is the fourth release candidate for 1.0. It fixes a few bugs in 1.0 Release
1039Candidate 3.
1040
1041## 1.0 Release Candidate 3
1042
1043This is the third release candidate for 1.0. It fixes a few bugs in 1.0 Release
1044Candidate 2.
1045
1046## 1.0 Release Candidate 2
1047
1048This is the second release candidate for 1.0. It fixes a few bugs in 1.0 Release
1049Candidate 1.
1050
1051## 1.0 Release Candidate 1
1052
1053This is the first Release Candidate for 1.0. `bc` is complete, with `dc`, but it
1054is not tested.
1055
1056## 0.5
1057
1058This beta release completes more features, but it is still not complete nor
1059tested as thoroughly as necessary.
1060
1061## 0.4.1
1062
1063This beta release fixes a few bugs in 0.4.
1064
1065## 0.4
1066
1067This is a beta release. It does not have the complete set of features, and it is
1068not thoroughly tested.
1069
1070[1]: https://docs.microsoft.com/en-us/windows/wsl/install-win10
1071[2]: https://pkg.musl.cc/bc/
1072[3]: http://lcamtuf.coredump.cx/afl/
1073[4]: ./karatsuba.py
1074[5]: ./README.md
1075[6]: ./configure.sh
1076[7]: https://github.com/rain-1/linenoise-mob
1077[8]: https://github.com/antirez/linenoise
1078[9]: ./manuals/bc/A.1.md
1079[10]: ./manuals/dc/A.1.md
1080[11]: https://scan.coverity.com/projects/gavinhoward-bc
1081[12]: ./locale_install.sh
1082[13]: ./manuals/build.md
1083[14]: https://github.com/stesser
1084[15]: https://github.com/bugcrazy
1085[16]: ./manuals/bc/A.1.md#extended-library
1086[17]: https://github.com/skeeto/optparse
1087[18]: https://www.deepl.com/translator
1088[19]: ./manuals/benchmarks.md
1089[20]: https://github.com/apjanke/ronn-ng
1090[21]: https://pandoc.org/
1091