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* Stamp 12.19.REL_12_19Tom Lane2024-05-06
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* Clean up Windows-specific mutex code in libpq and ecpglib.Tom Lane2024-02-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix pthread-win32.h and pthread-win32.c to provide a more complete emulation of POSIX pthread mutexes: define PTHREAD_MUTEX_INITIALIZER and make sure that pthread_mutex_lock() can operate on a mutex object that's been initialized that way. Then we don't need the duplicative platform-specific logic in default_threadlock() and pgtls_init(), which we'd otherwise need yet a third copy of for an upcoming bug fix. Also, since default_threadlock() supposes that pthread_mutex_lock() cannot fail, try to ensure that that's actually true, by getting rid of the malloc call that was formerly involved in initializing an emulated mutex. We can define an extra state for the spinlock field instead. Also, replace the similar code in ecpglib/misc.c with this version. While ecpglib's version at least had a POSIX-compliant API, it also had the potential of failing during mutex init (but here, because of CreateMutex failure rather than malloc failure). Since all of misc.c's callers ignore failures, it seems like a wise idea to avoid failures here too. A further improvement in this area could be to unify libpq's and ecpglib's implementations into a src/port/pthread-win32.c file. But that doesn't seem like a bug fix, so I'll desist for now. In preparation for the aforementioned bug fix, back-patch to all supported branches. Discussion: https://postgr.es/m/264860.1707163416@sss.pgh.pa.us
* Stamp 12.18.REL_12_18Tom Lane2024-02-05
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* Stamp 12.17.REL_12_17Tom Lane2023-11-06
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* Stamp 12.16.REL_12_16Tom Lane2023-08-07
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* Stamp 12.15.REL_12_15Tom Lane2023-05-08
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* Stamp 12.14.REL_12_14Tom Lane2023-02-06
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* Re-allow building on Microsoft Visual Studio 2013.Tom Lane2022-11-10
| | | | | | | | | | | | | | | | | | In commit 450ee7012 I supposed that all platforms we now care about have snprintf(), since that's required by C99. Turns out that Microsoft did not get around to adding that until VS2015. We've dropped support for VS2013 as of HEAD (cf 6203583b7), but not in the back branches, so add a hack for this in the back branches only. There's no easy shortcut to an exact emulation of standard snprintf in VS2013, but fortunately we don't need one: this code was just fine with using sprintf before 450ee7012, so we can make it do so again on that platform (and any others where the problem might crop up). Per bug #17681 from Daisuke Higuchi. Back-patch to v12, like the previous patch. Discussion: https://postgr.es/m/17681-485ba2ec13e7f392@postgresql.org
* Stamp 12.13.REL_12_13Tom Lane2022-11-07
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* Use libc's snprintf, not sprintf, for special cases in snprintf.c.Tom Lane2022-10-16
| | | | | | | | | | | | | | | | | | | | | | | | | | snprintf.c has always fallen back on libc's *printf implementation when printing pointers (%p) and floats. When this code originated, we were still supporting some platforms that lacked native snprintf, so we used sprintf for that. That's not actually unsafe in our usage, but nonetheless builds on macOS are starting to complain about sprintf being unconditionally deprecated; and I wouldn't be surprised if other platforms follow suit. There seems little reason to believe that any platform supporting C99 wouldn't have standards-compliant snprintf, so let's just use that instead to suppress such warnings. Back-patch to v12, which is where we started to require C99. It's also where we started to use our snprintf.c everywhere, so this wouldn't be enough to suppress the warning in older branches anyway --- that is, in older branches these aren't necessarily all our usages of libc's sprintf. It is enough in v12+ because any deprecation annotation attached to libc's sprintf won't apply to pg_sprintf. (Whether all our usages of pg_sprintf are adequately safe is not a matter I intend to address here, but perhaps it could do with some review.) Per report from Andres Freund and local testing. Discussion: https://postgr.es/m/20221015211955.q4cwbsfkyk3c4ty3@awork3.anarazel.de
* Include c.h instead of postgres.h in src/port/*p{read,write}*.cAndres Freund2022-09-17
| | | | | | | | Frontend code shouldn't include postgres.h. Some files in src/port/ need to include postgres.h/postgres_fe.h, but these files don't. Discussion: https://postgr.es/m/20220915022626.5xx3ccgkzpkqw5mq@awork3.anarazel.de Backpatch: 12-, where 3fd2a7932ef introduced (some) of these files
* Stamp 12.12.REL_12_12Tom Lane2022-08-08
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* Stamp 12.11.REL_12_11Tom Lane2022-05-09
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* Stamp 12.10.REL_12_10Tom Lane2022-02-07
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* Stamp 12.9.REL_12_9Tom Lane2021-11-08
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* Stamp 12.8.REL_12_8Tom Lane2021-08-09
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* Make printf("%s", NULL) print "(null)" instead of crashing.Tom Lane2021-07-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We previously took a hard-line attitude that callers should never print a null string pointer, and doing so is worthy of an assertion failure or crash. However, we've long since flushed out any easy-to-find bugs of that nature. What remains is a lot of code that perhaps could fail that way in hard-to-reach corner cases. For example, in something as simple as ereport(ERROR, (errcode(ERRCODE_UNDEFINED_OBJECT), errmsg("constraint \"%s\" for table \"%s\" does not exist", conname, get_rel_name(relid)))); one must wonder whether it's completely guaranteed that get_rel_name cannot return NULL in this context. If such a situation did occur, the existing policy converts what might be a pretty minor bug into a server crash condition. This is not good for robustness. Hence, let's follow the lead of glibc and print "(null)" instead of failing. We should, of course, still consider it a bug if that behavior is reachable in ordinary use; but crashing seems less desirable than not crashing. This fix works across-the-board in v12 and up, where we always use src/port/snprintf.c. Before that, on most platforms we're at the mercy of the local libc, but it appears that Solaris 10 is the only supported platform where we'd still get a crash. Most other platforms such as *BSD, macOS, and Solaris 11 have adopted glibc's behavior at some point. (AIX and HPUX just print "" not "(null)", but that's close enough.) I've not checked what Windows' native printf would do, but it doesn't matter because we've long used snprintf.c on that platform. In v12 and up, also const-ify related code so that we're not casting away const on the constant string. This is just neatnik-ism, since next to no compilers will warn about that. Discussion: https://postgr.es/m/17098-b960f3616c861f83@postgresql.org
* Add fallback implementation for setenv()Michael Paquier2021-06-01
| | | | | | | | | | | | | | | | This fixes the code compilation on Windows with MSVC and Kerberos, as a missing implementation of setenv() causes a compilation failure of the GSSAPI code. This was only reproducible when building the code with Kerberos, something that buildfarm animal hamerkop has fixed recently. This issue only happens on 12 and 13, as this code has been introduced in b0b39f7. HEAD is already able to compile properly thanks to 7ca37fb0, and this commit is a minimal cherry-pick of it. Thanks to Tom Lane for the discussion. Discussion: https://postgr.es/m/YLDtm5WGjPxm6ua4@paquier.xyz Backpatch-through: 12
* Stamp 12.7.REL_12_7Tom Lane2021-05-10
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* pg_attribute_no_sanitize_alignment() macroTom Lane2021-02-13
| | | | | | | | | | | | | | | | | Modern gcc and clang compilers offer alignment sanitizers, which help to detect pointer misalignment. However, our codebase already contains x86-specific crc32 computation code, which uses unalignment access. Thankfully, those compilers also support the attribute, which disables alignment sanitizers at the function level. This commit adds pg_attribute_no_sanitize_alignment(), which wraps this attribute, and applies it to pg_comp_crc32c_sse42() function. Back-patch of commits 993bdb9f9 and ad2ad698a, to enable doing alignment testing in all supported branches. Discussion: https://postgr.es/m/CAPpHfdsne3%3DT%3DfMNU45PtxdhSL_J2PjLTeS8rwKnJzUR4YNd4w%40mail.gmail.com Discussion: https://postgr.es/m/475514.1612745257%40sss.pgh.pa.us Author: Alexander Korotkov, revised by Tom Lane Reviewed-by: Tom Lane
* Stamp 12.6.REL_12_6Tom Lane2021-02-08
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* Stamp 12.5.REL_12_5Tom Lane2020-11-09
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* In the postmaster, rely on the signal infrastructure to block signals.Tom Lane2020-10-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | POSIX sigaction(2) can be told to block a set of signals while a signal handler executes. Make use of that instead of manually blocking and unblocking signals in the postmaster's signal handlers. This should save a few cycles, but more importantly it prevents recursive invocation of signal handlers when many signals arrive in close succession. (Assuming that the platform's signal infrastructure is designed to avoid consuming stack space in that case, but this is demonstrably true at least on Linux.) The existing code has been seen to recurse to the point of stack overflow, either in the postmaster or in a forked-off child. Back-patch of commit 9abb2bfc0. At the time, we'd only seen excess postmaster stack consumption in the buildfarm; but we now have a user report of it, and that commit has aged enough to have a fair amount of confidence that it doesn't break anything. This still doesn't change anything about the way that it works on Windows. Perhaps someone else would like to fix that? Per bug #16673 from David Geier. Back-patch to 9.6. Although the problem exists in principle before that, we've only seen it actually materialize in connection with heavy use of parallel workers, so it doesn't seem necessary to do anything in 9.5; and the relevant code is different there, too. Discussion: https://postgr.es/m/16673-d278c604f8e34ec0@postgresql.org Discussion: https://postgr.es/m/14878.1570820201@sss.pgh.pa.us
* Stamp 12.4.REL_12_4Tom Lane2020-08-10
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* Stamp 12.3.REL_12_3Tom Lane2020-05-11
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* Get rid of trailing semicolons in C macro definitions.Tom Lane2020-05-01
| | | | | | | | | | | | | | | | | | | | | | | Writing a trailing semicolon in a macro is almost never the right thing, because you almost always want to write a semicolon after each macro call instead. (Even if there was some reason to prefer not to, pgindent would probably make a hash of code formatted that way; so within PG the rule should basically be "don't do it".) Thus, if we have a semi inside the macro, the compiler sees "something;;". Much of the time the extra empty statement is harmless, but it could lead to mysterious syntax errors at call sites. In perhaps an overabundance of neatnik-ism, let's run around and get rid of the excess semicolons whereever possible. The only thing worse than a mysterious syntax error is a mysterious syntax error that only happens in the back branches; therefore, backpatch these changes where relevant, which is most of them because most of these mistakes are old. (The lack of reported problems shows that this is largely a hypothetical issue, but still, it could bite us in some future patch.) John Naylor and Tom Lane Discussion: https://postgr.es/m/CACPNZCs0qWTqJ2QUSGJ07B7uvAvzMb-KbG2q+oo+J3tsWN5cqw@mail.gmail.com
* Be more careful about extracting encoding from locale strings on Windows.Tom Lane2020-03-30
| | | | | | | | | | | | | | | | | | | | | GetLocaleInfoEx() can fail on strings that setlocale() was perfectly happy with. A common way for that to happen is if the locale string is actually a Unix-style string, say "et_EE.UTF-8". In that case, what's after the dot is an encoding name, not a Windows codepage number; blindly treating it as a codepage number led to failure, with a fairly silly error message. Hence, check to see if what's after the dot is all digits, and if not, treat it as a literal encoding name rather than a codepage number. This will do the right thing with many Unix-style locale strings, and produce a more sensible error message otherwise. Somewhat independently of that, treat a zero (CP_ACP) result from GetLocaleInfoEx() as meaning that we must use UTF-8 encoding. Back-patch to all supported branches. Juan José Santamaría Flecha Discussion: https://postgr.es/m/24905.1585445371@sss.pgh.pa.us
* Fix our getopt_long's behavior for a command line argument of just "-".Tom Lane2020-03-23
| | | | | | | | | | | | | | | | | | | src/port/getopt_long.c failed on such an argument, always seeing it as an unrecognized switch. This is unhelpful; better is to treat such an item as a non-switch argument. That behavior is what we find in GNU's getopt_long(); it's what src/port/getopt.c does; and it is required by POSIX for getopt(), which getopt_long() ought to be generally a superset of. Moreover, it's expected by ecpg, which intends an argument of "-" to mean "read from stdin". So fix it. Also add some documentation about ecpg's behavior in this area, since that was miserably underdocumented. I had to reverse-engineer it from the code. Per bug #16304 from James Gray. Back-patch to all supported branches, since this has been broken forever. Discussion: https://postgr.es/m/16304-c662b00a1322db7f@postgresql.org
* Stamp 12.2.REL_12_2Tom Lane2020-02-10
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* In pgwin32_open, loop after ERROR_ACCESS_DENIED only if we can't stat.Tom Lane2019-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes a performance problem introduced by commit 6d7547c21. ERROR_ACCESS_DENIED is returned in some other cases besides the delete-pending case considered by that commit; notably, if the given path names a directory instead of a plain file. In that case we'll uselessly loop for 1 second before returning the failure condition. That slows down some usage scenarios enough to cause test timeout failures on our Windows buildfarm critters. To fix, try to stat() the file, and sleep/loop only if that fails. It will fail in the delete-pending case, and also in the case where the deletion completed before we could stat(), so we have the cases where we want to loop covered. In the directory case, the stat() should succeed, letting us exit without a wait. One case where we'll still wait uselessly is if the access-denied problem pertains to a directory in the given pathname. But we don't expect that to happen in any performance-critical code path. There might be room to refine this further, but I'll push it now in hopes of making the buildfarm green again. Back-patch, like the preceding commit. Alexander Lakhin and Tom Lane Discussion: https://postgr.es/m/23073.1576626626@sss.pgh.pa.us
* On Windows, wait a little to see if ERROR_ACCESS_DENIED goes away.Tom Lane2019-12-16
| | | | | | | | | | | | | | | | | | | | | | | Attempting to open a file fails with ERROR_ACCESS_DENIED if the file is flagged for deletion but not yet actually gone (another in a long list of reasons why Windows is broken, if you ask me). This seems likely to explain a lot of irreproducible failures we see in the buildfarm. This state generally persists for only a millisecond or so, so just wait a bit and retry. If it's a real permissions problem, we'll eventually give up and report it as such. If it's the pending deletion case, we'll see file-not-found and report that after the deletion completes, and the caller will treat that in an appropriate way. In passing, rejigger the existing retry logic for some other error cases so that we don't uselessly wait an extra time when we're not going to retry anymore. Alexander Lakhin (with cosmetic tweaks by me). Back-patch to all supported branches, since this seems like a pretty safe change and the problem is definitely real. Discussion: https://postgr.es/m/16161-7a985d2f1bbe8f71@postgresql.org
* Handle ReadFile() EOF correctly on Windows.Thomas Munro2019-11-20
| | | | | | | | | | | | | | | | When ReadFile() encounters the end of a file while reading from a synchronous handle with an offset provided via OVERLAPPED, it reports an error instead of returning 0. By not handling that (undocumented) result correctly, we caused some noisy LOG messages about an unknown error code. Repair. Back-patch to 12, where we started using pread()/ReadFile() with an offset. Reported-by: ZhenHua Cai, Amit Kapila Diagnosed-by: Juan Jose Santamaria Flecha Tested-by: Amit Kapila Discussion: https://postgr.es/m/CAA4eK1LK3%2BWRtpz68TiRdpHwxxWm%3D%2Bt1BMf-G68hhQsAQ41PZg%40mail.gmail.com
* Stamp 12.1.REL_12_1Tom Lane2019-11-11
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* Deal with yet another issue related to "Norwegian (Bokmål)" locale.Tom Lane2019-10-21
| | | | | | | | | | | | | It emerges that recent versions of Windows (at least 2016 Standard) spell this locale name as "Norwegian Bokmål_Norway.1252", defeating our mapping code that translates "Norwegian (Bokmål)_Norway" to something that's all-ASCII (cf commits db29620d4 and aa1d2fc5e). Add another mapping entry to handle this spelling. Per bug #16068 from Robert Ford. Like the previous patches, back-patch to all supported branches. Discussion: https://postgr.es/m/16068-4cb6eeaa7eb46d93@postgresql.org
* Improve what pg_strsignal prints if we haven't got strsignal(3).Tom Lane2019-08-27
| | | | | | | | | | Turns out that returning "unrecognized signal" is confusing. Make it explicit that the platform lacks any support for signal names. (At least of the machines in the buildfarm, only HPUX lacks it.) Back-patch to v12 where we invented this function. Discussion: https://postgr.es/m/3067.1566870481@sss.pgh.pa.us
* Fix more typos and inconsistencies in the treeMichael Paquier2019-06-17
| | | | | Author: Alexander Lakhin Discussion: https://postgr.es/m/0a5419ea-1452-a4e6-72ff-545b1a5a8076@gmail.com
* Fix typos and inconsistencies in code commentsMichael Paquier2019-06-14
| | | | | Author: Alexander Lakhin Discussion: https://postgr.es/m/dec6aae8-2d63-639f-4d50-20e229fb83e3@gmail.com
* Phase 2 pgindent run for v12.Tom Lane2019-05-22
| | | | | | | | | Switch to 2.1 version of pg_bsd_indent. This formats multiline function declarations "correctly", that is with additional lines of parameter declarations indented to match where the first line's left parenthesis is. Discussion: https://postgr.es/m/CAEepm=0P3FeTXRcU5B2W3jv3PgRVZ-kGUXLGfd42FFhUROO3ug@mail.gmail.com
* Initial pgindent run for v12.Tom Lane2019-05-22
| | | | | | | | This is still using the 2.0 version of pg_bsd_indent. I thought it would be good to commit this separately, so as to document the differences between 2.0 and 2.1 behavior. Discussion: https://postgr.es/m/16296.1558103386@sss.pgh.pa.us
* ANSI-ify a few straggler K&R-style function definitions.Tom Lane2019-05-18
| | | | | | | | We still had a couple of these left in ancient src/port/ files. Convert them to modern style in preparation for switching to a version of pg_bsd_indent that doesn't cope well with K&R style. Discussion: https://postgr.es/m/16886.1558104483@sss.pgh.pa.us
* Assert that pgwin32_signal_initialize() has been called early enough.Noah Misch2019-04-03
| | | | | | | | Before the pgwin32_signal_initialize() call, the backend version of pg_usleep() has no effect. No in-tree code falls afoul of that today, but temporary commit 23078689a9921968ac0873b017be6e7f772f10bc did so. Discussion: https://postgr.es/m/20190402135442.GA1173872@rfd.leadboat.com
* Fix error handling of readdir() port implementation on first file lookupMichael Paquier2019-03-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | The implementation of readdir() in src/port/ which gets used by MSVC has been added in 399a36a, and since the beginning it considers all errors on the first file lookup as ENOENT, setting errno accordingly and letting the routine caller think that the directory is empty. While this is normally enough for the case of the backend, this can confuse callers of this routine on Windows as all errors would map to the same behavior. So, for example, even permission errors would be thought as having an empty directory, while there could be contents in it. This commit changes the error handling so as readdir() gets a behavior similar to native implementations: force errno=0 when seeing ERROR_FILE_NOT_FOUND as error and consider other errors as plain failures. While looking at the patch, I noticed that MinGW does not enforce errno=0 when looking at the first file, but it gets enforced on the next file lookups. A comment related to that was incorrect in the code. Reported-by: Yuri Kurenkov Diagnosed-by: Yuri Kurenkov, Grigory Smolkin Author: Konstantin Knizhnik Reviewed-by: Andrew Dunstan, Michael Paquier Discussion: https://postgr.es/m/2cad7829-8d66-e39c-b937-ac825db5203d@postgrespro.ru Backpatch-through: 9.4
* Make use of compiler builtins and/or assembly for CLZ, CTZ, POPCNT.Tom Lane2019-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Test for the compiler builtins __builtin_clz, __builtin_ctz, and __builtin_popcount, and make use of these in preference to handwritten C code if they're available. Create src/port infrastructure for "leftmost one", "rightmost one", and "popcount" so as to centralize these decisions. On x86_64, __builtin_popcount generally won't make use of the POPCNT opcode because that's not universally supported yet. Provide code that checks CPUID and then calls POPCNT via asm() if available. This requires indirecting through a function pointer, which is an annoying amount of overhead for a one-instruction operation, but it's probably not worth working harder than this for our current use-cases. I'm not sure we've found all the existing places that could profit from this new infrastructure; but we at least touched all the ones that used copied-and-pasted versions of the bitmapset.c code, and got rid of multiple copies of the associated constant arrays. While at it, replace c-compiler.m4's one-per-builtin-function macros with a single one that can handle all the cases we need to worry about so far. Also, because I'm paranoid, make those checks into AC_LINK checks rather than just AC_COMPILE; the former coding failed to verify that libgcc has support for the builtin, in cases where it's not inline code. David Rowley, Thomas Munro, Alvaro Herrera, Tom Lane Discussion: https://postgr.es/m/CAKJS1f9WTAGG1tPeJnD18hiQW5gAk59fQ6WK-vfdAKEHyRg2RA@mail.gmail.com
* Cygwin and Mingw floating-point fixes.Andrew Gierth2019-02-16
| | | | | | | | | | | | | | Deal with silent-underflow errors in float4 for cygwin and mingw by using our strtof() wrapper; deal with misrounding errors by adding them to the resultmap. Some slight reorganization of declarations was done to avoid duplicating material between cygwin.h and win32_port.h. While here, remove from the resultmap all references to float8-small-is-zero; inspection of cygwin output suggests it's no longer required there, and the freebsd/netbsd/openbsd entries should no longer be necessary (these date back to c. 2000). This commit doesn't remove the file itself nor the documentation references for it; that will happen in a subsequent commit if all goes well.
* Revert attempts to use POPCNT etc instructionsAlvaro Herrera2019-02-15
| | | | | | | | | | | This reverts commits fc6c72747ae6, 109de05cbb03, d0b4663c23b7 and 711bab1e4d19. Somebody will have to try harder before submitting this patch again. I've spent entirely too much time on it already, and the #ifdef maze yet to be written in order for it to build at all got on my nerves. The amount of work needed to get a platform-specific performance improvement that's barely above the noise level is not worth it.
* Fix compiler builtin usage in new pg_bitutils.cAlvaro Herrera2019-02-15
| | | | | | | | | | | | | | | | | | | | | | Split out these new functions in three parts: one in a new file that uses the compiler builtin and gets compiled with the -mpopcnt compiler option if it exists; another one that uses the compiler builtin but not the compiler option; and finally the fallback with open-coded algorithms. Split out the configure logic: in the original commit, it was selecting to use the -mpopcnt compiler switch together with deciding whether to use the compiler builtin, but those two things are really separate. Split them out. Also, expose whether the builtin exists to Makefile.global, so that src/port's Makefile can decide whether to compile the hw-optimized file. Remove CPUID test for CTZ/CLZ. Make pg_{right,left}most_ones use either the compiler intrinsic or open-coded algo; trying to use the HW-optimized version is a waste of time. Make them static inline functions. Discussion: https://postgr.es/m/20190213221719.GA15976@alvherre.pgsql
* Fix portability issues in pg_bitutilsAlvaro Herrera2019-02-13
| | | | | | | | | | | | | | | We were using uint64 function arguments as "long int" arguments to compiler builtins, which fails on machines where long ints are 32 bits: the upper half of the uint64 was being ignored. Fix by using the "ll" builtin variants instead, which on those machines take 64 bit arguments. Also, remove configure tests for __builtin_popcountl() (as well as "long" variants for ctz and clz): the theory here is that any compiler version will provide all widths or none, so one test suffices. Were this theory to be wrong, we'd have to add tests for __builtin_popcountll() and friends, which would be tedious. Per failures in buildfarm member lapwing and ensuing discussion.
* Add -mpopcnt to all compiles of pg_bitutils.cAlvaro Herrera2019-02-13
| | | | The way this makefile works, we need to specify it three times.
* Add basic support for using the POPCNT and SSE4.2s LZCNT opcodesAlvaro Herrera2019-02-13
| | | | | | | | | | | | | These opcodes have been around in the AMD world since 2007, and 2008 in the case of intel. They're supported in GCC and Clang via some __builtin macros. The opcodes may be unavailable during runtime, in which case we fall back on a C-based implementation of the code. In order to get the POPCNT instruction we must pass the -mpopcnt option to the compiler. We do this only for the pg_bitutils.c file. David Rowley (with fragments taken from a patch by Thomas Munro) Discussion: https://postgr.es/m/CAKJS1f9WTAGG1tPeJnD18hiQW5gAk59fQ6WK-vfdAKEHyRg2RA@mail.gmail.com
* Use strtof() and not strtod() for float4 input.Andrew Gierth2019-02-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | Using strtod() creates a double-rounding problem; the input decimal value is first rounded to the nearest double; rounding that to the nearest float may then give an incorrect result. An example is that 7.038531e-26 when input via strtod and then rounded to float4 gives 0xAE43FEp-107 instead of the correct 0xAE43FDp-107. Values output by earlier PG versions with extra_float_digits=3 should all be read in with the same values as previously. However, values supplied by other software using shortest representations could be mis-read. On platforms that lack a strtof() entirely, we fall back to the old incorrect rounding behavior. (As strtof() is required by C99, such platforms are considered of primarily historical interest.) On VS2013, some workarounds are used to get correct error handling. The regression tests now test for the correct input values, so platforms that lack strtof() will need resultmap entries. An entry for HP-UX 10 is included (more may be needed). Reviewed-By: Tom Lane Discussion: https://postgr.es/m/871s5emitx.fsf@news-spur.riddles.org.uk Discussion: https://postgr.es/m/87d0owlqpv.fsf@news-spur.riddles.org.uk
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