xref: /freebsd/contrib/bc/NEWS.md (revision 32100375a661c1e16588ddfa7b90ca8d26cb9786)
1# News
2
3## 3.0.2
4
5This is a production release that adds `utf8` locale symlinks and removes an
6unused `auto` variable from the `ceil()` function in the [extended math
7library][16].
8
9Users do ***NOT*** need to update unless they want the locales.
10
11## 3.0.1
12
13This is a production release with two small changes. Users do ***NOT*** need to
14upgrade to this release; however, if they haven't upgraded to `3.0.0` yet, it
15may be worthwhile to upgrade to this release.
16
17The first change is fixing a compiler warning on FreeBSD with strict warnings
18on.
19
20The second change is to make the new implementation of `ceil()` in `lib2.bc`
21much more efficient.
22
23## 3.0.0
24
25*Notes for package maintainers:*
26
27*First, the `2.7.0` release series saw a change in the option parsing. This made
28me change one error message and add a few others. The error message that was
29changed removed one format specifier. This means that `printf()` will seqfault
30on old locale files. Unfortunately, `bc` cannot use any locale files except the
31global ones that are already installed, so it will use the previous ones while
32running tests during install. **If `bc` segfaults while running arg tests when
33updating, it is because the global locale files have not been replaced. Make
34sure to either prevent the test suite from running on update or remove the old
35locale files before updating.** Once this is done, `bc` should install without
36problems.*
37
38*Second, **the option to build without signal support has been removed**. See
39below for the reasons why.*
40
41This is a production release with some small bug fixes, a few improvements,
42three major bug fixes, and a complete redesign of `bc`'s error and signal
43handling. **Users and package maintainers should update to this version as soon
44as possible.**
45
46The first major bug fix was in how `bc` executed files. Previously, a whole file
47was parsed before it was executed, but if a function is defined *after* code,
48especially if the function definition was actually a redefinition, and the code
49before the definition referred to the previous function, this `bc` would replace
50the function before executing any code. The fix was to make sure that all code
51that existed before a function definition was executed.
52
53The second major bug fix was in `bc`'s `lib2.bc`. The `ceil()` function had a
54bug where a `0` in the decimal place after the truncation position, caused it to
55output the wrong numbers if there was any non-zero digit after.
56
57The third major bug is that when passing parameters to functions, if an
58expression included an array (not an array element) as a parameter, it was
59accepted, when it should have been rejected. It is now correctly rejected.
60
61Beyond that, this `bc` got several improvements that both sped it up, improved
62the handling of signals, and improved the error handling.
63
64First, the requirements for `bc` were pushed back to POSIX 2008. `bc` uses one
65function, `strdup()`, which is not in POSIX 2001, and it is in the X/Open System
66Interfaces group 2001. It is, however, in POSIX 2008, and since POSIX 2008 is
67old enough to be supported anywhere that I care, that should be the requirement.
68
69Second, the BcVm global variable was put into `bss`. This actually slightly
70reduces the size of the executable from a massive code shrink, and it will stop
71`bc` from allocating a large set of memory when `bc` starts.
72
73Third, the default Karatsuba length was updated from 64 to 32 after making the
74optimization changes below, since 32 is going to be better than 64 after the
75changes.
76
77Fourth, Spanish translations were added.
78
79Fifth, the interpreter received a speedup to make performance on non-math-heavy
80scripts more competitive with GNU `bc`. While improvements did, in fact, get it
81much closer (see the [benchmarks][19]), it isn't quite there.
82
83There were several things done to speed up the interpreter:
84
85First, several small inefficiencies were removed. These inefficiencies included
86calling the function `bc_vec_pop(v)` twice instead of calling
87`bc_vec_npop(v, 2)`. They also included an extra function call for checking the
88size of the stack and checking the size of the stack more than once on several
89operations.
90
91Second, since the current `bc` function is the one that stores constants and
92strings, the program caches pointers to the current function's vectors of
93constants and strings to prevent needing to grab the current function in order
94to grab a constant or a string.
95
96Third, `bc` tries to reuse `BcNum`'s (the internal representation of
97arbitary-precision numbers). If a `BcNum` has the default capacity of
98`BC_NUM_DEF_SIZE` (32 on 64-bit and 16 on 32-bit) when it is freed, it is added
99to a list of available `BcNum`'s. And then, when a `BcNum` is allocated with a
100capacity of `BC_NUM_DEF_SIZE` and any `BcNum`'s exist on the list of reusable
101ones, one of those ones is grabbed instead.
102
103In order to support these changes, the `BC_NUM_DEF_SIZE` was changed. It used to
104be 16 bytes on all systems, but it was changed to more closely align with the
105minimum allocation size on Linux, which is either 32 bytes (64-bit musl), 24
106bytes (64-bit glibc), 16 bytes (32-bit musl), or 12 bytes (32-bit glibc). Since
107these are the minimum allocation sizes, these are the sizes that would be
108allocated anyway, making it worth it to just use the whole space, so the value
109of `BC_NUM_DEF_SIZE` on 64-bit systems was changed to 32 bytes.
110
111On top of that, at least on 64-bit, `BC_NUM_DEF_SIZE` supports numbers with
112either 72 integer digits or 45 integer digits and 27 fractional digits. This
113should be more than enough for most cases since `bc`'s default `scale` values
114are 0 or 20, meaning that, by default, it has at most 20 fractional digits. And
11545 integer digits are *a lot*; it's enough to calculate the amount of mass in
116the Milky Way galaxy in kilograms. Also, 72 digits is enough to calculate the
117diameter of the universe in Planck lengths.
118
119(For 32-bit, these numbers are either 32 integer digits or 12 integer digits and
12020 fractional digits. These are also quite big, and going much bigger on a
12132-bit system seems a little pointless since 12 digits in just under a trillion
122and 20 fractional digits is still enough for about any use since `10^-20` light
123years is just under a millimeter.)
124
125All of this together means that for ordinary uses, and even uses in scientific
126work, the default number size will be all that is needed, which means that
127nearly all, if not all, numbers will be reused, relieving pressure on the system
128allocator.
129
130I did several experiments to find the changes that had the most impact,
131especially with regard to reusing `BcNum`'s. One was putting `BcNum`'s into
132buckets according to their capacity in powers of 2 up to 512. That performed
133worse than `bc` did in `2.7.2`. Another was putting any `BcNum` on the reuse
134list that had a capacity of `BC_NUM_DEF_SIZE * 2` and reusing them for `BcNum`'s
135that requested `BC_NUM_DEF_SIZE`. This did reduce the amount of time spent, but
136it also spent a lot of time in the system allocator for an unknown reason. (When
137using `strace`, a bunch more `brk` calls showed up.) Just reusing `BcNum`'s that
138had exactly `BC_NUM_DEF_SIZE` capacity spent the smallest amount of time in both
139user and system time. This makes sense, especially with the changes to make
140`BC_NUM_DEF_SIZE` bigger on 64-bit systems, since the vast majority of numbers
141will only ever use numbers with a size less than or equal to `BC_NUM_DEF_SIZE`.
142
143Last of all, `bc`'s signal handling underwent a complete redesign. (This is the
144reason that this version is `3.0.0` and not `2.8.0`.) The change was to move
145from a polling approach to signal handling to an interrupt-based approach.
146
147Previously, every single loop condition had a check for signals. I suspect that
148this could be expensive when in tight loops.
149
150Now, the signal handler just uses `longjmp()` (actually `siglongjmp()`) to start
151an unwinding of the stack until it is stopped or the stack is unwound to
152`main()`, which just returns. If `bc` is currently executing code that cannot be
153safely interrupted (according to POSIX), then signals are "locked." The signal
154handler checks if the lock is taken, and if it is, it just sets the status to
155indicate that a signal arrived. Later, when the signal lock is released, the
156status is checked to see if a signal came in. If so, the stack unwinding starts.
157
158This design eliminates polling in favor of maintaining a stack of `jmp_buf`'s.
159This has its own performance implications, but it gives better interaction. And
160the cost of pushing and popping a `jmp_buf` in a function is paid at most twice.
161Most functions do not pay that price, and most of the rest only pay it once.
162(There are only some 3 functions in `bc` that push and pop a `jmp_buf` twice.)
163
164As a side effect of this change, I had to eliminate the use of `stdio.h` in `bc`
165because `stdio` does not play nice with signals and `longjmp()`. I implemented
166custom I/O buffer code that takes a fraction of the size. This means that static
167builds will be smaller, but non-static builds will be bigger, though they will
168have less linking time.
169
170This change is also good because my history implementation was already bypassing
171`stdio` for good reasons, and unifying the architecture was a win.
172
173Another reason for this change is that my `bc` should *always* behave correctly
174in the presence of signals like `SIGINT`, `SIGTERM`, and `SIGQUIT`. With the
175addition of my own I/O buffering, I needed to also make sure that the buffers
176were correctly flushed even when such signals happened.
177
178For this reason, I **removed the option to build without signal support**.
179
180As a nice side effect of this change, the error handling code could be changed
181to take advantage of the stack unwinding that signals used. This means that
182signals and error handling use the same code paths, which means that the stack
183unwinding is well-tested. (Errors are tested heavily in the test suite.)
184
185It also means that functions do not need to return a status code that
186***every*** caller needs to check. This eliminated over 100 branches that simply
187checked return codes and then passed that return code up the stack if necessary.
188The code bloat savings from this is at least 1700 bytes on `x86_64`, *before*
189taking into account the extra code from removing `stdio.h`.
190
191## 2.7.2
192
193This is a production release with one major bug fix.
194
195The `length()` built-in function can take either a number or an array. If it
196takes an array, it returns the length of the array. Arrays can be passed by
197reference. The bug is that the `length()` function would not properly
198dereference arrays that were references. This is a bug that affects all users.
199
200**ALL USERS SHOULD UPDATE `bc`**.
201
202## 2.7.1
203
204This is a production release with fixes for new locales and fixes for compiler
205warnings on FreeBSD.
206
207## 2.7.0
208
209This is a production release with a bug fix for Linux, new translations, and new
210features.
211
212Bug fixes:
213
214* Option parsing in `BC_ENV_ARGS` was broken on Linux in 2.6.1 because `glibc`'s
215  `getopt_long()` is broken. To get around that, and to support long options on
216  every platform, an adapted version of [`optparse`][17] was added. Now, `bc`
217  does not even use `getopt()`.
218* Parsing `BC_ENV_ARGS` with quotes now works. It isn't the smartest, but it
219  does the job if there are spaces in file names.
220
221The following new languages are supported:
222
223* Dutch
224* Polish
225* Russian
226* Japanes
227* Simplified Chinese
228
229All of these translations were generated using [DeepL][18], so improvements are
230welcome.
231
232There is only one new feature: **`bc` now has a built-in pseudo-random number
233generator** (PRNG).
234
235The PRNG is seeded, making it useful for applications where
236`/dev/urandom` does not work because output needs to be reproducible. However,
237it also uses `/dev/urandom` to seed itself by default, so it will start with a
238good seed by default.
239
240It also outputs 32 bits on 32-bit platforms and 64 bits on 64-bit platforms, far
241better than the 15 bits of C's `rand()` and `bash`'s `$RANDOM`.
242
243In addition, the PRNG can take a bound, and when it gets a bound, it
244automatically adjusts to remove bias. It can also generate numbers of arbitrary
245size. (As of the time of release, the largest pseudo-random number generated by
246this `bc` was generated with a bound of `2^(2^20)`.)
247
248***IMPORTANT: read the [`bc` manual][9] and the [`dc` manual][10] to find out
249exactly what guarantees the PRNG provides. The underlying implementation is not
250guaranteed to stay the same, but the guarantees that it provides are guaranteed
251to stay the same regardless of the implementation.***
252
253On top of that, four functions were added to `bc`'s [extended math library][16]
254to make using the PRNG easier:
255
256* `frand(p)`: Generates a number between `[0,1)` to `p` decimal places.
257* `ifrand(i, p)`: Generates an integer with bound `i` and adds it to `frand(p)`.
258* `srand(x)`: Randomizes the sign of `x`. In other words, it flips the sign of
259  `x` with probability `0.5`.
260* `brand()`: Returns a random boolean value (either `0` or `1`).
261
262## 2.6.1
263
264This is a production release with a bug fix for FreeBSD.
265
266The bug was that when `bc` was built without long options, it would give a fatal
267error on every run. This was caused by a mishandling of `optind`.
268
269## 2.6.0
270
271This release is a production release ***with no bugfixes***. If you do not want
272to upgrade, you don't have to.
273
274No source code changed; the only thing that changed was `lib2.bc`.
275
276This release adds one function to the [extended math library][16]: `p(x, y)`,
277which calculates `x` to the power of `y`, whether or not `y` is an integer. (The
278`^` operator can only accept integer powers.)
279
280This release also includes a couple of small tweaks to the [extended math
281library][16], mostly to fix returning numbers with too high of `scale`.
282
283## 2.5.3
284
285This release is a production release which addresses inconsistencies in the
286Portuguese locales. No `bc` code was changed.
287
288The issues were that the ISO files used different naming, and also that the
289files that should have been symlinks were not. I did not catch that because
290GitHub rendered them the exact same way.
291
292## 2.5.2
293
294This release is a production release.
295
296No code was changed, but the build system was changed to allow `CFLAGS` to be
297given to `CC`, like this:
298
299```
300CC="gcc -O3 -march=native" ./configure.sh
301```
302
303If this happens, the flags are automatically put into `CFLAGS`, and the compiler
304is set appropriately. In the example above this means that `CC` will be "gcc"
305and `CFLAGS` will be "-O3 -march=native".
306
307This behavior was added to conform to GNU autotools practices.
308
309## 2.5.1
310
311This is a production release which addresses portability concerns discovered
312in the `bc` build system. No `bc` code was changed.
313
314* Support for Solaris SPARC and AIX were added.
315* Minor documentations edits were performed.
316* An option for `configure.sh` was added to disable long options if
317  `getopt_long()` is missing.
318
319## 2.5.0
320
321This is a production release with new translations. No code changed.
322
323The translations were contributed by [bugcrazy][15], and they are for
324Portuguese, both Portugal and Brazil locales.
325
326## 2.4.0
327
328This is a production release primarily aimed at improving `dc`.
329
330* A couple of copy and paste errors in the [`dc` manual][10] were fixed.
331* `dc` startup was optimized by making sure it didn't have to set up `bc`-only
332  things.
333* The `bc` `&&` and `||` operators were made available to `dc` through the `M`
334  and `m` commands, respectively.
335* `dc` macros were changed to be tail call-optimized.
336
337The last item, tail call optimization, means that if the last thing in a macro
338is a call to another macro, then the old macro is popped before executing the
339new macro. This change was made to stop `dc` from consuming more and more memory
340as macros are executed in a loop.
341
342The `q` and `Q` commands still respect the "hidden" macros by way of recording
343how many macros were removed by tail call optimization.
344
345## 2.3.2
346
347This is a production release meant to fix warnings in the Gentoo `ebuild` by
348making it possible to disable binary stripping. Other users do *not* need to
349upgrade.
350
351## 2.3.1
352
353This is a production release. It fixes a bug that caused `-1000000000 < -1` to
354return `0`. This only happened with negative numbers and only if the value on
355the left was more negative by a certain amount. That said, this bug *is* a bad
356bug, and needs to be fixed.
357
358**ALL USERS SHOULD UPDATE `bc`**.
359
360## 2.3.0
361
362This is a production release with changes to the build system.
363
364## 2.2.0
365
366This release is a production release. It only has new features and performance
367improvements.
368
3691.	The performance of `sqrt(x)` was improved.
3702.	The new function `root(x, n)` was added to the extended math library to
371	calculate `n`th roots.
3723.	The new function `cbrt(x)` was added to the extended math library to
373	calculate cube roots.
374
375## 2.1.3
376
377This is a non-critical release; it just changes the build system, and in
378non-breaking ways:
379
3801.	Linked locale files were changed to link to their sources with a relative
381	link.
3822.	A bug in `configure.sh` that caused long option parsing to fail under `bash`
383	was fixed.
384
385## 2.1.2
386
387This release is not a critical release.
388
3891.	A few codes were added to history.
3902.	Multiplication was optimized a bit more.
3913.	Addition and subtraction were both optimized a bit more.
392
393## 2.1.1
394
395This release contains a fix for the test suite made for Linux from Scratch: now
396the test suite prints `pass` when a test is passed.
397
398Other than that, there is no change in this release, so distros and other users
399do not need to upgrade.
400
401## 2.1.0
402
403This release is a production release.
404
405The following bugs were fixed:
406
4071.	A `dc` bug that caused stack mishandling was fixed.
4082.	A warning on OpenBSD was fixed.
4093.	Bugs in `ctrl+arrow` operations in history were fixed.
4104.	The ability to paste multiple lines in history was added.
4115.	A `bc` bug, mishandling of array arguments to functions, was fixed.
4126.	A crash caused by freeing the wrong pointer was fixed.
4137.	A `dc` bug where strings, in a rare case, were mishandled in parsing was
414	fixed.
415
416In addition, the following changes were made:
417
4181.	Division was slightly optimized.
4192.	An option was added to the build to disable printing of prompts.
4203.	The special case of empty arguments is now handled. This is to prevent
421	errors in scripts that end up passing empty arguments.
4224.	A harmless bug was fixed. This bug was that, with the pop instructions
423	(mostly) removed (see below), `bc` would leave extra values on its stack for
424	`void` functions and in a few other cases. These extra items would not
425	affect anything put on the stack and would not cause any sort of crash or
426	even buggy behavior, but they would cause `bc` to take more memory than it
427	needed.
428
429On top of the above changes, the following optimizations were added:
430
4311.	The need for pop instructions in `bc` was removed.
4322.	Extra tests on every iteration of the interpreter loop were removed.
4333.	Updating function and code pointers on every iteration of the interpreter
434	loop was changed to only updating them when necessary.
4354.	Extra assignments to pointers were removed.
436
437Altogether, these changes sped up the interpreter by around 2x.
438
439***NOTE***: This is the last release with new features because this `bc` is now
440considered complete. From now on, only bug fixes and new translations will be
441added to this `bc`.
442
443## 2.0.3
444
445This is a production, bug-fix release.
446
447Two bugs were fixed in this release:
448
4491.	A rare and subtle signal handling bug was fixed.
4502.	A misbehavior on `0` to a negative power was fixed.
451
452The last bug bears some mentioning.
453
454When I originally wrote power, I did not thoroughly check its error cases;
455instead, I had it check if the first number was `0` and then if so, just return
456`0`. However, `0` to a negative power means that `1` will be divided by `0`,
457which is an error.
458
459I caught this, but only after I stopped being cocky. You see, sometime later, I
460had noticed that GNU `bc` returned an error, correctly, but I thought it was
461wrong simply because that's not what my `bc` did. I saw it again later and had a
462double take. I checked for real, finally, and found out that my `bc` was wrong
463all along.
464
465That was bad on me. But the bug was easy to fix, so it is fixed now.
466
467There are two other things in this release:
468
4691.	Subtraction was optimized by [Stefan Eßer][14].
4702.	Division was also optimized, also by Stefan Eßer.
471
472## 2.0.2
473
474This release contains a fix for a possible overflow in the signal handling. I
475would be surprised if any users ran into it because it would only happen after 2
476billion (`2^31-1`) `SIGINT`'s, but I saw it and had to fix it.
477
478## 2.0.1
479
480This release contains very few things that will apply to any users.
481
4821.	A slight bug in `dc`'s interactive mode was fixed.
4832.	A bug in the test suite that was only triggered on NetBSD was fixed.
4843.	**The `-P`/`--no-prompt` option** was added for users that do not want a
485	prompt.
4864.	A `make check` target was added as an alias for `make test`.
4875.	`dc` got its own read prompt: `?> `.
488
489## 2.0.0
490
491This release is a production release.
492
493This release is also a little different from previous releases. From here on
494out, I do not plan on adding any more features to this `bc`; I believe that it
495is complete. However, there may be bug fix releases in the future, if I or any
496others manage to find bugs.
497
498This release has only a few new features:
499
5001.	`atan2(y, x)` was added to the extended math library as both `a2(y, x)` and
501	`atan2(y, x)`.
5022.	Locales were fixed.
5033.	A **POSIX shell-compatible script was added as an alternative to compiling
504	`gen/strgen.c`** on a host machine. More details about making the choice
505	between the two can be found by running `./configure.sh --help` or reading
506	the [build manual][13].
5074.	Multiplication was optimized by using **diagonal multiplication**, rather
508	than straight brute force.
5095.	The `locale_install.sh` script was fixed.
5106.	`dc` was given the ability to **use the environment variable
511	`DC_ENV_ARGS`**.
5127.	`dc` was also given the ability to **use the `-i` or `--interactive`**
513	options.
5148.	Printing the prompt was fixed so that it did not print when it shouldn't.
5159.	Signal handling was fixed.
51610.	**Handling of `SIGTERM` and `SIGQUIT`** was fixed.
51711.	The **built-in functions `maxibase()`, `maxobase()`, and `maxscale()`** (the
518	commands `T`, `U`, `V` in `dc`, respectively) were added to allow scripts to
519	query for the max allowable values of those globals.
52012.	Some incompatibilities with POSIX were fixed.
521
522In addition, this release is `2.0.0` for a big reason: the internal format for
523numbers changed. They used to be a `char` array. Now, they are an array of
524larger integers, packing more decimal digits into each integer. This has
525delivered ***HUGE*** performance improvements, especially for multiplication,
526division, and power.
527
528This `bc` should now be the fastest `bc` available, but I may be wrong.
529
530## 1.2.8
531
532This release contains a fix for a harmless bug (it is harmless in that it still
533works, but it just copies extra data) in the [`locale_install.sh`][12] script.
534
535## 1.2.7
536
537This version contains fixes for the build on Arch Linux.
538
539## 1.2.6
540
541This release removes the use of `local` in shell scripts because it's not POSIX
542shell-compatible, and also updates a man page that should have been updated a
543long time ago but was missed.
544
545## 1.2.5
546
547This release contains some missing locale `*.msg` files.
548
549## 1.2.4
550
551This release contains a few bug fixes and new French translations.
552
553## 1.2.3
554
555This release contains a fix for a bug: use of uninitialized data. Such data was
556only used when outputting an error message, but I am striving for perfection. As
557Michelangelo said, "Trifles make perfection, and perfection is no trifle."
558
559## 1.2.2
560
561This release contains fixes for OpenBSD.
562
563## 1.2.1
564
565This release contains bug fixes for some rare bugs.
566
567## 1.2.0
568
569This is a production release.
570
571There have been several changes since `1.1.0`:
572
5731.	The build system had some changes.
5742.	Locale support has been added. (Patches welcome for translations.)
5753.	**The ability to turn `ibase`, `obase`, and `scale` into stacks** was added
576	with the `-g` command-line option. (See the [`bc` manual][9] for more
577	details.)
5784.	Support for compiling on Mac OSX out of the box was added.
5795.	The extended math library got `t(x)`, `ceil(x)`, and some aliases.
5806.	The extended math library also got `r2d(x)` (for converting from radians to
581	degrees) and `d2r(x)` (for converting from degrees to radians). This is to
582	allow using degrees with the standard library.
5837.	Both calculators now accept numbers in **scientific notation**. See the
584	[`bc` manual][9] and the [`dc` manual][10] for details.
5858.	Both calculators can **output in either scientific or engineering
586	notation**. See the [`bc` manual][9] and the [`dc` manual][10] for details.
5879.	Some inefficiencies were removed.
58810.	Some bugs were fixed.
58911.	Some bugs in the extended library were fixed.
59012.	Some defects from [Coverity Scan][11] were fixed.
591
592## 1.1.4
593
594This release contains a fix to the build system that allows it to build on older
595versions of `glibc`.
596
597## 1.1.3
598
599This release contains a fix for a bug in the test suite where `bc` tests and
600`dc` tests could not be run in parallel.
601
602## 1.1.2
603
604This release has a fix for a history bug; the down arrow did not work.
605
606## 1.1.1
607
608This release fixes a bug in the `1.1.0` build system. The source is exactly the
609same.
610
611The bug that was fixed was a failure to install if no `EXECSUFFIX` was used.
612
613## 1.1.0
614
615This is a production release. However, many new features were added since `1.0`.
616
6171.	**The build system has been changed** to use a custom, POSIX
618	shell-compatible configure script ([`configure.sh`][6]) to generate a POSIX
619	make-compatible `Makefile`, which means that `bc` and `dc` now build out of
620	the box on any POSIX-compatible system.
6212.	Out-of-memory and output errors now cause the `bc` to report the error,
622	clean up, and die, rather than just reporting and trying to continue.
6233.	**Strings and constants are now garbage collected** when possible.
6244.	Signal handling and checking has been made more simple and more thorough.
6255.	`BcGlobals` was refactored into `BcVm` and `BcVm` was made global. Some
626	procedure names were changed to reflect its difference to everything else.
6276.	Addition got a speed improvement.
6287.	Some common code for addition and multiplication was refactored into its own
629	procedure.
6308.	A bug was removed where `dc` could have been selected, but the internal
631	`#define` that returned `true` for a query about `dc` would not have
632	returned `true`.
6339.	Useless calls to `bc_num_zero()` were removed.
63410.	**History support was added.** The history support is based off of a
635	[UTF-8 aware fork][7] of [`linenoise`][8], which has been customized with
636	`bc`'s own data structures and signal handling.
63711.	Generating C source from the math library now removes tabs from the library,
638	shrinking the size of the executable.
63912.	The math library was shrunk.
64013.	Error handling and reporting was improved.
64114.	Reallocations were reduced by giving access to the request size for each
642	operation.
64315.	**`abs()` (`b` command for `dc`) was added as a builtin.**
64416.	Both calculators were tested on FreeBSD.
64517.	Many obscure parse bugs were fixed.
64618.	Markdown and man page manuals were added, and the man pages are installed by
647	`make install`.
64819.	Executable size was reduced, though the added features probably made the
649	executable end up bigger.
65020.	**GNU-style array references were added as a supported feature.**
65121.	Allocations were reduced.
65222.	**New operators were added**: `$` (`$` for `dc`), `@` (`@` for `dc`), `@=`,
653	`<<` (`H` for `dc`), `<<=`, `>>` (`h` for `dc`), and `>>=`. See the
654	[`bc` manual][9] and the [`dc` manual][10] for more details.
65523.	**An extended math library was added.** This library contains code that
656	makes it so I can replace my desktop calculator with this `bc`. See the
657	[`bc` manual][3] for more details.
65824.	Support for all capital letters as numbers was added.
65925.	**Support for GNU-style void functions was added.**
66026.	A bug fix for improper handling of function parameters was added.
66127.	Precedence for the or (`||`) operator was changed to match GNU `bc`.
66228.	`dc` was given an explicit negation command.
66329.	`dc` was changed to be able to handle strings in arrays.
664
665## 1.1 Release Candidate 3
666
667This release is the eighth release candidate for 1.1, though it is the third
668release candidate meant as a general release candidate. The new code has not
669been tested as thoroughly as it should for release.
670
671## 1.1 Release Candidate 2
672
673This release is the seventh release candidate for 1.1, though it is the second
674release candidate meant as a general release candidate. The new code has not
675been tested as thoroughly as it should for release.
676
677## 1.1 FreeBSD Beta 5
678
679This release is the sixth release candidate for 1.1, though it is the fifth
680release candidate meant specifically to test if `bc` works on FreeBSD. The new
681code has not been tested as thoroughly as it should for release.
682
683## 1.1 FreeBSD Beta 4
684
685This release is the fifth release candidate for 1.1, though it is the fourth
686release candidate meant specifically to test if `bc` works on FreeBSD. The new
687code has not been tested as thoroughly as it should for release.
688
689## 1.1 FreeBSD Beta 3
690
691This release is the fourth release candidate for 1.1, though it is the third
692release candidate meant specifically to test if `bc` works on FreeBSD. The new
693code has not been tested as thoroughly as it should for release.
694
695## 1.1 FreeBSD Beta 2
696
697This release is the third release candidate for 1.1, though it is the second
698release candidate meant specifically to test if `bc` works on FreeBSD. The new
699code has not been tested as thoroughly as it should for release.
700
701## 1.1 FreeBSD Beta 1
702
703This release is the second release candidate for 1.1, though it is meant
704specifically to test if `bc` works on FreeBSD. The new code has not been tested as
705thoroughly as it should for release.
706
707## 1.1 Release Candidate 1
708
709This is the first release candidate for 1.1. The new code has not been tested as
710thoroughly as it should for release.
711
712## 1.0
713
714This is the first non-beta release. `bc` is ready for production use.
715
716As such, a lot has changed since 0.5.
717
7181.	`dc` has been added. It has been tested even more thoroughly than `bc` was
719	for `0.5`. It does not have the `!` command, and for security reasons, it
720	never will, so it is complete.
7212.	`bc` has been more thoroughly tested. An entire section of the test suite
722	(for both programs) has been added to test for errors.
7233.	A prompt (`>>> `) has been added for interactive mode, making it easier to
724	see inputs and outputs.
7254.	Interrupt handling has been improved, including elimination of race
726	conditions (as much as possible).
7275.	MinGW and [Windows Subsystem for Linux][1] support has been added (see
728	[xstatic][2] for binaries).
7296.	Memory leaks and errors have been eliminated (as far as ASan and Valgrind
730	can tell).
7317.	Crashes have been eliminated (as far as [afl][3] can tell).
7328.	Karatsuba multiplication was added (and thoroughly) tested, speeding up
733	multiplication and power by orders of magnitude.
7349.	Performance was further enhanced by using a "divmod" function to reduce
735	redundant divisions and by removing superfluous `memset()` calls.
73610.	To switch between Karatsuba and `O(n^2)` multiplication, the config variable
737	`BC_NUM_KARATSUBA_LEN` was added. It is set to a sane default, but the
738	optimal number can be found with [`karatsuba.py`][4] (requires Python 3)
739	and then configured through `make`.
74011.	The random math test generator script was changed to Python 3 and improved.
741	`bc` and `dc` have together been run through 30+ million random tests.
74212.	All known math bugs have been fixed, including out of control memory
743	allocations in `sine` and `cosine` (that was actually a parse bug), certain
744	cases of infinite loop on square root, and slight inaccuracies (as much as
745	possible; see the [README][5]) in transcendental functions.
74613.	Parsing has been fixed as much as possible.
74714.	Test coverage was improved to 94.8%. The only paths not covered are ones
748	that happen when `malloc()` or `realloc()` fails.
74915.	An extension to get the length of an array was added.
75016.	The boolean not (`!`) had its precedence change to match negation.
75117.	Data input was hardened.
75218.	`bc` was made fully compliant with POSIX when the `-s` flag is used or
753	`POSIXLY_CORRECT` is defined.
75419.	Error handling was improved.
75520.	`bc` now checks that files it is given are not directories.
756
757## 1.0 Release Candidate 7
758
759This is the seventh release candidate for 1.0. It fixes a few bugs in 1.0
760Release Candidate 6.
761
762## 1.0 Release Candidate 6
763
764This is the sixth release candidate for 1.0. It fixes a few bugs in 1.0 Release
765Candidate 5.
766
767## 1.0 Release Candidate 5
768
769This is the fifth release candidate for 1.0. It fixes a few bugs in 1.0 Release
770Candidate 4.
771
772## 1.0 Release Candidate 4
773
774This is the fourth release candidate for 1.0. It fixes a few bugs in 1.0 Release
775Candidate 3.
776
777## 1.0 Release Candidate 3
778
779This is the third release candidate for 1.0. It fixes a few bugs in 1.0 Release
780Candidate 2.
781
782## 1.0 Release Candidate 2
783
784This is the second release candidate for 1.0. It fixes a few bugs in 1.0 Release
785Candidate 1.
786
787## 1.0 Release Candidate 1
788
789This is the first Release Candidate for 1.0. `bc` is complete, with `dc`, but it
790is not tested.
791
792## 0.5
793
794This beta release completes more features, but it is still not complete nor
795tested as thoroughly as necessary.
796
797## 0.4.1
798
799This beta release fixes a few bugs in 0.4.
800
801## 0.4
802
803This is a beta release. It does not have the complete set of features, and it is
804not thoroughly tested.
805
806[1]: https://docs.microsoft.com/en-us/windows/wsl/install-win10
807[2]: https://pkg.musl.cc/bc/
808[3]: http://lcamtuf.coredump.cx/afl/
809[4]: ./karatsuba.py
810[5]: ./README.md
811[6]: ./configure.sh
812[7]: https://github.com/rain-1/linenoise-mob
813[8]: https://github.com/antirez/linenoise
814[9]: ./manuals/bc.1.ronn
815[10]: ./manuals/dc.1.ronn
816[11]: https://scan.coverity.com/projects/gavinhoward-bc
817[12]: ./locale_install.sh
818[13]: ./manuals/build.md
819[14]: https://github.com/stesser
820[15]: https://github.com/bugcrazy
821[16]: ./manuals/bc.1.ronn#extended-library
822[17]: https://github.com/skeeto/optparse
823[18]: https://www.deepl.com/translator
824[19]: ./manuals/benchmarks.md
825