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2015-10-27Require GCC 4.7 or later to build glibc.Joseph Myers1-0/+4
This patch implements a requirement of GCC 4.7 or later to build glibc. This was discussed in the thread starting at <https://sourceware.org/ml/libc-alpha/2015-08/msg00851.html>. Concerns were expressed by Mike and David. At <https://sourceware.org/ml/libc-alpha/2015-10/msg00453.html> I have provided a 14-patch series showing in outline the cleanups facilitated by this version requirement, as requested by Mike (this patch is the first in that series, with the addition of a NEWS entry). Given the absence of further concerns or alternative proposals for criteria for updates to this version requirement as requested in <https://sourceware.org/ml/libc-alpha/2015-10/msg00065.html>, I am interpreting this as "absence of sustained opposition" under Carlos's definition at <https://sourceware.org/glibc/wiki/Consensus> and proposing this patch for inclusion in glibc. I'd like to remind people testing with 4.6 that if they move to testing with GCC 5 then it will probably be about four years before they need to update the compiler they use to test glibc again. Although on the principles of time-based updates I think a move to requiring binutils 2.23 would be reasonable, I'm not currently aware of any cleanups that would facilitate so am not proposing that at this time (but would expect to propose a move to requiring binutils 2.24 in a year's time, as that brings features such as AVX512 support that should allow some conditionals to be cleaned up). If someone thinks a move to requiring 2.23 would help clean things up for their architecture, please speak up. (And in general, I suspect there are lots of architecture-specific configure tests that could be removed on the basis of current GCC and binutils version requirements, given how I've found architecture-independent tests obsolete on the basis of version requirements going back 20 years.) Tested for x86_64 and x86 (testsuite, and that installed shared libraries are unchanged by the patch). * configure.ac (libc_cv_compiler_ok): Require GCC 4.7 or later. * configure: Regenerated. * manual/install.texi (Tools for Compilation): Document requirement for GCC 4.7 or later. * INSTALL: Regenerated.
2015-10-23Fix j1, jn missing errno setting on underflow (bug 18611).Joseph Myers1-9/+9
j1 and jn can underflow for small arguments, but fail to set errno when underflowing to 0. This patch fixes them to set errno in that case. Tested for x86_64, x86, mips64 and powerpc. [BZ #18611] * sysdeps/ieee754/dbl-64/e_j1.c (__ieee754_j1): Set errno and avoid excess range and precision on underflow. * sysdeps/ieee754/dbl-64/e_jn.c (__ieee754_jn): Likewise. * sysdeps/ieee754/flt-32/e_j1f.c (__ieee754_j1f): Likewise. * sysdeps/ieee754/flt-32/e_jnf.c (__ieee754_jnf): Likewise. * sysdeps/ieee754/ldbl-128/e_j1l.c (__ieee754_j1l): Set errno on underflow. * sysdeps/ieee754/ldbl-128/e_jnl.c (__ieee754_jnl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_jnl.c (__ieee754_jnl): Likewise. * sysdeps/ieee754/ldbl-96/e_j1l.c (__ieee754_j1l): Likewise. * sysdeps/ieee754/ldbl-96/e_jnl.c (__ieee754_jnl): Likewise. * math/auto-libm-test-in: Do not allow missing errno setting for tests of j1 and jn. * math/auto-libm-test-out: Regenerated.
2015-10-22Fix i386 / x86_64 nearbyint exception clearing (bug 15491).Joseph Myers1-12/+12
The implementations of nearbyint functions using x87 floating point (i386 all versions, x86_64 long double only) use the fclex instruction, which clears any exceptions that were raised before the function was called. These functions must not clear exceptions that were raised before they were called. This patch fixes these functions to save and restore the whole floating-point environment (fnstenv / fldenv) as the way of avoiding raising "inexact" (recall that there isn't an x87 instruction for loading just the status word, so the whole environment has to be saved and loaded instead - the code already saved and loaded the control word, which is now obtained from the saved environment after this patch, to disable traps on "inexact"). In the case of the long double functions, any "invalid" exception from frndint (applied to a signaling NaN) needs merging into the saved state; this issue doesn't apply to the float and double functions because that exception would have been raised when the argument is loaded, before the environment is saved. [BZ #15491] * sysdeps/i386/fpu/s_nearbyint.S (__nearbyint): Save and restore floating-point environment instead of clearing all exceptions. * sysdeps/i386/fpu/s_nearbyintf.S (__nearbyintf): Likewise. * sysdeps/i386/fpu/s_nearbyintl.S (__nearbyintl): Likewise, merging in "invalid" exceptions from frndint. * sysdeps/x86_64/fpu/s_nearbyintl.S (__nearbyintl): Likewise. * math/test-nearbyint-except.c: New file. * math/Makefile (tests): Add test-nearbyint-except.
2015-10-22Update NEWS to mention drive-by fix for bug 18699.Chris Metcalf1-7/+8
Wilco fixed this tilegx bug in commit fe8c2b33aed0 ("Since we now inline isinf, isnan and isfinite in math.h, replace uses of __isinf_ns(l/f) with isinf, and remove the unused inlines __isinf_ns(l/f), __isnan(f) and __finite(f).") I verified that reverting math/s_cprojf.c back to using the sysdeps/ieee754/flt-32/math_private.h version of __isinf_nsf() instead of isinf() brings back the bug on tilegx.
2015-10-21Fix ldbl-128 j0l spurious underflows (bug 19156).Joseph Myers1-1/+1
My recent addition of more tests for j0 showed up that the ldbl-128 implementation of j0l produces spurious underflow exceptions for arguments close to 0 (when the result is very close to 1). This patch fixes this by just returning the argument in that case. Tested for mips64 (where it fixes the recently-added tests that were previously failing). [BZ #19156] * sysdeps/ieee754/ldbl-128/e_j0l.c (__ieee754_j0l): Return 1 for arguments very close to 0.
2015-10-19PowerPC: Fix a race condition when eliding a lockTulio Magno Quites Machado Filho1-7/+7
The previous code used to evaluate the preprocessor token is_lock_free to a variable before starting a transaction. This behavior can cause an error if another thread got the lock (without using a transaction) between the evaluation of the token and the beginning of the transaction. This bug can be triggered with the following order of events: 1. The lock accessed by is_lock_free is free. 2. Thread T1 evaluates is_lock_free and stores into register R1 that the lock is free. 3. Thread T2 acquires the same lock used in is_lock_free. 4. T1 begins the transaction, creating a memory barrier where is_lock_free is false, but R1 is true. 5. T1 reads R1 and doesn't abort the transaction. 6. T1 calls ELIDE_UNLOCK, which reads false from is_lock_free and decides to unlock a lock acquired by T2, leading to undefined behavior. This patch delays the evaluation of is_lock_free to inside a transaction by moving this part of the code to the macro ELIDE_LOCK. [BZ #18743] * sysdeps/powerpc/nptl/elide.h (__elide_lock): Move most of this code to... (ELIDE_LOCK): ...here. (__get_new_count): New function with part of the code from __elide_lock that updates the value of adapt_count after a transaction abort. (__elided_trylock): Moved this code to... (ELIDE_TRYLOCK): ...here.
2015-10-19timezone: document new --disable-timezone-tools optionMike Frysinger1-0/+5
Reported-by: Joseph Myers <joseph@codesourcery.com>
2015-10-17The va_list pointer is unspecified after a call to vfprintf [BZ #18982]Florian Weimer1-3/+3
This adjusts the documentation to the existing implementation.
2015-10-17lt_LT: change currency symbol to the euro [BZ #18953]Gunnar Hjalmarsson1-4/+4
Lithuania switched currency to the Euro on 1st Jan 2015.
2015-10-17hu_HU: change time separator to colon [BZ #18918]Egmont Koblinger1-5/+5
The previous (11th) version of the Hungarian spelling rules (released in 1984) said that the separator had to be a dot, e.g. 10.35 meaning 10 o'clock 35 minutes. glibc correctly implements this. The brand new (12th) version, in effect since September 1, 2015 adopts to the common use of colon (especially in the digital world) and allows to use either separator, without even expressing a preference. For computer systems, using colons is way more typical and probably easier to recognize. Dot is typically used in printed materials. It also avoids an almost ambiguous situation where a space makes a difference, e.g. "10.15-ig" means "until 10 o'clock 15 minutes" whereas "10. 15-ig" means "until 15th of October". So I believe using the colon as the separator is not only more frequent in the computer world, but is also easier and quicker to recognize for the brain that it's about hour:minute rather than month and day. And luckily it's now equally correct according to the official rules. 11th edition: http://helyesiras.mta.hu/helyesiras/default/akh11 12th edition: http://helyesiras.mta.hu/helyesiras/default/akh12 In both editions it's the very last (299th and 300th, respectively) rule. Microsoft also uses and recommends a colon since at least May 2011: http://download.microsoft.com/download/e/6/1/e61266b2-d8b4-4fe0-a553-f01dc3976675/hun-hun-StyleGuide.pdf The time format is different in common language and in the language of IT. In common texts we usually do not abbreviate, so the full forms are used: “7 óra 10 perckor csörgött a telefon”. However, the short format, consisting of numerals only, can also be used. In this case a period must be used between the two numbers and there must not be a space between them: “találkozzunk 10.45-kor”. However, in software mostly the short format is used, and the numbers are separated by a colon. An obvious example is the clock in the bottom right corner of your screen, thus 18:31.
2015-10-15Remove i386/epoll_pwait.SH.J. Lu1-1/+1
Only i386 implements epoll_pwait in assembly code withot cancellation support. All other architectures implement epoll_pwait in epoll_pwait.c with int epoll_pwait (int epfd, struct epoll_event *events, int maxevents, int timeout, const sigset_t *set) { return SYSCALL_CANCEL (epoll_pwait, epfd, events, maxevents, timeout, set, _NSIG / 8); } Although there is no test for epoll_pwait in glibc, since SYSCALL_CANCEL works on i386 and epoll_pwait.c works for other architectures, it is safe to assume that epoll_pwait.c with SYSCALL_CANCEL also works on i386. [BZ #19137] * sysdeps/unix/sysv/linux/i386/Makefile (CFLAGS-epoll_pwait.c): Add -fomit-frame-pointer. * sysdeps/unix/sysv/linux/i386/epoll_pwait.S: Remove file.
2015-10-15Always enable pointer guard [BZ #18928]Florian Weimer1-5/+8
Honoring the LD_POINTER_GUARD environment variable in AT_SECURE mode has security implications. This commit enables pointer guard unconditionally, and the environment variable is now ignored. [BZ #18928] * sysdeps/generic/ldsodefs.h (struct rtld_global_ro): Remove _dl_pointer_guard member. * elf/rtld.c (_rtld_global_ro): Remove _dl_pointer_guard initializer. (security_init): Always set up pointer guard. (process_envvars): Do not process LD_POINTER_GUARD.
2015-10-14Fix powerpc32 lround, lroundf spurious exceptions (bug 19134).Joseph Myers1-1/+1
The powerpc32 implementation of lround and lroundf can produce spurious exceptions from adding 0.5 then converting to integer. This includes "inexact" from the conversion to integer (not allowed for integer arguments to these functions), and, for larger integer arguments, "inexact", and "overflow" when rounding upward, from the addition. In addition, "inexact" is not allowed together with "invalid" and so inexact addition must be avoided when the integer will be out of range of 32-bit long, whether or not the argument is an integer. This patch fixes these problems. As in the powerpc64 llround implementation, a check is added for too-large arguments; in the powerpc64 case that means arguments at least 2^52 in magnitude (so that 0.5 cannot be added exactly), while in this case it means arguments for which the result would overflow "long". In those cases a suitable overflowing value is used for the integer conversion without adding 0.5, while for smaller arguments it's tested whether the argument is an integer (by adding and subtracting 2^52 to the absolute value and comparing with the original absolute value) to avoid adding 0.5 to integers and generating spurious "inexact". This code is not used when the power5+ sysdeps directories are used, as there's a separate power5+ version of these functions.. Tested for powerpc. This gets test-float (for a default powerpc32 hard-float build without any --with-cpu) back to the point where it should pass once powerpc ulps are regenerated; test-double still needs another problem with exceptions fixed to get back to that point (and I haven't looked lately at what default powerpc64 results are like). [BZ #19134] * sysdeps/powerpc/powerpc32/fpu/s_lround.S (.LC1): New object. (.LC2): Likewise. (.LC3): Likewise. (__lround): Do not add 0.5 to integer or out-of-range arguments.
2015-10-14[BZ #19129][ARM] Fix _dl_tlsdesc_resolve_hold to save r0Szabolcs Nagy1-1/+1
_dl_tlsdesc_resolve_hold calls into a C function that clobbers r0, but it assumes the original argument is still in r0 after the call. This can cause crash in case of concurrent TLS access when TLSDESC is in use (-mtls-dialect=gnu2). Run into this while fixing BZ 18572. Both r0 and r1 are saved/restored so the stack remains 8 byte aligned. [BZ #19129] * sysdeps/arm/dl-tlsdesc.S (_dl_tlsdesc_resolve_hold): Save and restore r0 and r1.
2015-10-14Fix double-checked locking in _res_hconf_reorder_addrs [BZ #19074]Florian Weimer1-2/+3
[BZ #19074] * resolv/res_hconf.c (_res_hconf_reorder_addrs): Use atomics to load and store num_ifs.
2015-10-14Support PLT and GOT references in local PIC checkH.J. Lu1-3/+3
Linker in binutils 2.26 and newer generate GOT references instead PLT references when -z now is passed to linker. We need to extend scripts/localplt.awk to allow PLT or GOT references. [BZ #19007] * scripts/localplt.awk: Also allow GOT references. * sysdeps/unix/sysv/linux/i386/localplt.data: Mark _Unwind_Find_FDE, calloc, memalign, realloc and __libc_memalign with "+ REL R_386_GLOB_DAT". * sysdeps/x86_64/localplt.data: Mark calloc, memalign, realloc and __libc_memalign with "+ RELA R_X86_64_GLOB_DAT".
2015-10-13Fix powerpc32 llround, llroundf exceptions (bug 19125).Joseph Myers1-1/+1
The powerpc32 implementations of llroundf and llround produce spurious and missing exceptions (some arising from such exceptions from conversions to long long, some present even when fctidz is used). This patch fixes those problems in a similar way to the llrint / llrintf fixes. The spurious exceptions in the fctidz case for large arguments arise from a converted value that saturated as LLONG_MAX being converted back to float or double (the conversion back being inexact, but "inexact" must not be raised together with "invalid"), and from the subtraction x - xrf also being inexact for sufficiently large arguments (whether the saturation was to LLONG_MAX or LLONG_MIN); those are fixed by returning early if the argument is large enough that no rounding is needed. This code is not used for --with-cpu=power4 builds (I suspect the code used in that case may also produce spurious "inexact" exceptions, but that's something to investigate later). Tested for powerpc. [BZ #19125] * sysdeps/powerpc/powerpc32/fpu/s_llround.c: Include <limits.h>, <math_private.h> and <stdint.h>. (__llround): Avoid conversions to and from long long int, and subtractions, where those might raise spurious exceptions. * sysdeps/powerpc/powerpc32/fpu/s_llroundf.c: Include <math_private.h> and <stdint.h>. (__llroundf): Avoid conversions to and from long long int, and subtractions, where those might raise spurious exceptions.
2015-10-13Support x86-64 assmebler without AVX512H.J. Lu1-1/+1
When x86-64 assmebler doesn't support AVX512, we should make _dl_runtime_resolve_avx512/_dl_runtime_profile_avx512 as aliases of _dl_runtime_resolve_avx/_dl_runtime_profile_avx. Tested on x86-64 using GCC 5.2 with binutils 20151008 and GCC 4.8 with binutils 20130219. There are no differences in ld.so with binutils 20151008. There are no unexpected failures with binutils 20130219 and 20151008. [BZ #19124] * sysdeps/x86_64/dl-trampoline.S [!HAVE_AVX512_ASM_SUPPORT] (_dl_runtime_resolve_avx512): Make it a hidden alias of _dl_runtime_resolve_avx. (_dl_runtime_profile_avx512): Make it a hidden alias of _dl_runtime_profile_avx.
2015-10-13Fix powerpc32 llrint, llrintf bad exceptions (bug 16422).Joseph Myers1-10/+10
The versions of llrint and llrintf for older powerpc32 processors convert the results of __rint / __rintf to long long int, resulting in spurious exceptions from such casts in certain cases. This patch makes glibc work around the problems with the libgcc conversions when the compiler used to build glibc doesn't use the fctidz instruction for them. Tested for powerpc. [BZ #16422] * sysdeps/powerpc/powerpc32/fpu/configure.ac (libc_cv_ppc_fctidz): New configure test. * sysdeps/powerpc/powerpc32/fpu/configure: Regenerated. * config.h.in [_LIBC] (HAVE_PPC_FCTIDZ): New macro. * sysdeps/powerpc/powerpc32/fpu/s_llrint.c: Include <limits.h>, <math_private.h> and <stdint.h>. (__llrint): Avoid conversions to long long int where those might raise spurious exceptions. * sysdeps/powerpc/powerpc32/fpu/s_llrintf.c: Include <math_private.h> and <stdint.h>. (__llrintf): Avoid conversions to long long int where those might raise spurious exceptions.
2015-10-09Fix llrint, llround missing exceptions for ARM (bug 15470).Joseph Myers1-10/+10
Similar to the recent fix for MIPS, ARM is also missing correct exceptions on overflow from llrint and llround functions because casts from floating-point types to long long do not result in correct exceptions on overflow. This patch enables the fix for this for ARM. Tested for ARM. [BZ #15470] * sysdeps/arm/fix-fp-int-convert-overflow.h: New file.
2015-10-09Fix lrint, llrint, lround, llround missing exceptions for MIPS (bug 16399).Joseph Myers1-10/+10
For 32-bit MIPS and some other systems, various of the lrint, llrint, lround, llround functions can be missing exceptions on overflow because casts do not (in current GCC) result in the proper exceptions. In the MIPS case there are two problems here: MIPS I code generation uses an assembler macro that doesn't raise exceptions, while the libgcc conversions of floating-point values to long long also do not raise "invalid" on all overflow cases (and can raise spurious "inexact"). This patch adds support in the generic code (only the functions for which this problem has actually been seen) for forcing the "invalid" exception in the problem cases, and enables that support for the affected MIPS cases. Tested for MIPS; also tested for x86_64 and x86 that installed stripped shared libraries are unchanged by this patch. [BZ #16399] * sysdeps/generic/fix-fp-int-convert-overflow.h: New file. * sysdeps/ieee754/dbl-64/s_llrint.c: Include <fenv.h>, <limits.h> and <fix-fp-int-convert-overflow.h>. (__llrint) [FE_INVALID]: Force FE_INVALID exception as needed if FIX_DBL_LLONG_CONVERT_OVERFLOW. * sysdeps/ieee754/dbl-64/s_llround.c: Include <fenv.h>, <limits.h> and <fix-fp-int-convert-overflow.h>. (__llround) [FE_INVALID]: Force FE_INVALID exception as needed if FIX_DBL_LLONG_CONVERT_OVERFLOW. * sysdeps/ieee754/dbl-64/s_lrint.c: Include <fix-fp-int-convert-overflow.h>. (__lrint) [FE_INVALID]: Force FE_INVALID exception as needed if FIX_DBL_LLONG_CONVERT_OVERFLOW. * sysdeps/ieee754/dbl-64/s_lround.c: Include <fix-fp-int-convert-overflow.h>. (__lround) [FE_INVALID]: Force FE_INVALID exception as needed if FIX_DBL_LLONG_CONVERT_OVERFLOW. * sysdeps/ieee754/flt-32/s_llrintf.c: Include <fenv.h>, <limits.h> and <fix-fp-int-convert-overflow.h>. (__llrintf) [FE_INVALID]: Force FE_INVALID exception as needed if FIX_DBL_LLONG_CONVERT_OVERFLOW. * sysdeps/ieee754/flt-32/s_llroundf.c: Include <fenv.h>, <limits.h> and <fix-fp-int-convert-overflow.h>. (__llroundf) [FE_INVALID]: Force FE_INVALID exception as needed if FIX_DBL_LLONG_CONVERT_OVERFLOW. * sysdeps/ieee754/flt-32/s_lrintf.c: Include <fenv.h>, <limits.h> and <fix-fp-int-convert-overflow.h>. (__lrintf) [FE_INVALID]: Force FE_INVALID exception as needed if FIX_DBL_LLONG_CONVERT_OVERFLOW. * sysdeps/ieee754/flt-32/s_lroundf.c: Include <fenv.h>, <limits.h> and <fix-fp-int-convert-overflow.h>. (__lroundf) [FE_INVALID]: Force FE_INVALID exception as needed if FIX_DBL_LLONG_CONVERT_OVERFLOW. * sysdeps/mips/mips32/fpu/fix-fp-int-convert-overflow.h: New file.
2015-10-09Fix dbl-64 lrint for 64-bit long (bug 19095).Joseph Myers1-1/+1
The dbl-64 implementation of lrint produces incorrect results for some arguments with 64-bit long because a 32-bit (unsigned) low part of the mantissa is shifted left, losing high bits in the process. This patch fixes this by casting to long int before shifting, as in lround (as this case only applies for 64-bit long, there are no issues with sign-extension). Tested for mips64 (n64). [BZ #19095] * sysdeps/ieee754/dbl-64/s_lrint.c (__lrint): Cast low part of mantissa to long int before shifting left.
2015-10-08Fix lrint, llrint missing exceptions close to overflow threshold (bug 19094).Joseph Myers1-1/+1
The dbl-64, ldbl-96 and ldbl-128 implementations of lrint and llrint fail to produce "invalid" exceptions in cases where the rounded result overflows the target type, but truncating the floating-point argument to the next integer towards zero does not overflow it (so in particular casts do not produce such exceptions). (This issue cannot arise for float, or for double with 64-bit target type, or for ldbl-96 with 64-bit target type and negative arguments, because of insufficient precision in the floating-point type for arguments with the relevant property to exist. It also obviously cannot arise in FE_TOWARDZERO mode.) This patch fixes these problems by inserting checks for the special cases that can occur in each implementation, and explicitly raising FE_INVALID (and avoiding the cast if it might raise spurious FE_INEXACT, while raising FE_INEXACT explicitly in the cases where it is needed; unlike lround and llround, FE_INEXACT is required, not optional, for these functions for a within-range inexact result). The fixes are conditional on FE_INVALID or FE_INEXACT being defined. If any future architecture supports one but not both of those exceptions, the code will fail to compile and need fixing to handle that case (this seemed better than conditioning on both macros being defined, resulting in code that would compile but quietly miss exceptions on such a system). Tested for x86_64, x86 and mips64. Tested the ldbl-96 changes (only relevant for ia64, it appears) on x86_64 by removing the x86_64 versions of lrintl / llrintl. [BZ #19094] * sysdeps/ieee754/dbl-64/s_lrint.c: Include <fenv.h> and <limits.h>. (__lrint) [FE_INVALID || FE_INEXACT]: Force FE_INVALID exception when result overflows but exception would not result from cast. * sysdeps/ieee754/ldbl-128/s_llrintl.c: Include <fenv.h> and <limits.h>. (__llrintl) [FE_INVALID || FE_INEXACT]: Force FE_INVALID exception when result overflows but exception would not result from cast. * sysdeps/ieee754/ldbl-128/s_lrintl.c: Include <fenv.h> and <limits.h>. (__lrintl) [FE_INVALID || FE_INEXACT]: Force FE_INVALID exception when result overflows but exception would not result from cast. * sysdeps/ieee754/ldbl-96/s_llrintl.c: Include <fenv.h> and <limits.h>. (__llrintl) [FE_INVALID || FE_INEXACT]: Force FE_INVALID exception when result overflows but exception would not result from cast. * sysdeps/ieee754/ldbl-96/s_lrintl.c: Include <fenv.h> and <limits.h>. (__lrintl) [FE_INVALID || FE_INEXACT]: Force FE_INVALID exception when result overflows but exception would not result from cast. * math/libm-test.inc (lrint_test_data): Add more tests. (llrint_test_data): Likewise.
2015-10-08strcoll: Remove incorrect STRDIFF-based optimization (Bug 18589).Carlos O'Donell1-7/+7
The optimization introduced in commit f13c2a8dff2329c6692a80176262ceaaf8a6f74e, causes regressions in sorting for languages that have digraphs that change sort order, like cs_CZ which sorts ch between h and i. My analysis shows the fast-forwarding optimization in STRCOLL advances through a digraph while possibly stopping in the middle which results in a subsequent skipping of the digraph and incorrect sorting. The optimization is incorrect as implemented and because of that I'm removing it for 2.23, and I will also commit this fix for 2.22 where it was originally introduced. This patch reverts the optimization, introduces a new bug-strcoll2.c regression test that tests both cs_CZ.UTF-8 and da_DK.ISO-8859-1 and ensures they sort one digraph each correctly. The optimization can't be applied without regressing this test. Checked on x86_64, bug-strcoll2.c fails without this patch and passes after. This will also get a fix on 2.22 which has the same bug.
2015-10-08Add BZ#19086 to NEWS.Carlos O'Donell1-1/+2
2015-10-07Fix lround, llround missing exceptions close to overflow threshold (bug 19088).Joseph Myers1-1/+1
The dbl-64, ldbl-96 and ldbl-128 implementations of lround and llround fail to produce "invalid" exceptions in cases where the rounded result overflows the target type, but truncating the floating-point argument to the next integer towards zero does not overflow it (so in particular casts do not produce such exceptions). (This issue cannot arise for float, or for double with 64-bit target type, or for ldbl-96 with 64-bit target type and negative arguments, because of insufficient precision in the floating-point type for arguments with the relevant property to exist.) This patch fixes these problems by inserting checks for the special cases that can occur in each implementation, and explicitly raising FE_INVALID (and avoiding the cast if it might raise spurious FE_INEXACT). Tested for x86_64, x86 and mips64. [BZ #19088] * sysdeps/ieee754/dbl-64/s_lround.c: Include <fenv.h> and <limits.h>. (__lround) [FE_INVALID]: Force FE_INVALID exception when result overflows but exception would not result from cast. * sysdeps/ieee754/dbl-64/wordsize-64/s_lround.c: Include <fenv.h> and <limits.h>. (__lround) [FE_INVALID]: Force FE_INVALID exception when result overflows but exception would not result from cast. * sysdeps/ieee754/ldbl-128/s_llroundl.c: Include <fenv.h> and <limits.h>. (__llroundl) [FE_INVALID]: Force FE_INVALID exception when result overflows but exception would not result from cast. * sysdeps/ieee754/ldbl-128/s_lroundl.c: Include <fenv.h> and <limits.h>. (__lroundl) [FE_INVALID]: Force FE_INVALID exception when result overflows but exception would not result from cast. * sysdeps/ieee754/ldbl-96/s_llroundl.c: Include <fenv.h> and <limits.h>. (__llroundl) [FE_INVALID]: Force FE_INVALID exception when result overflows but exception would not result from cast. * sysdeps/ieee754/ldbl-96/s_lroundl.c: Include <fenv.h> and <limits.h>. (__lroundl) [FE_INVALID]: Force FE_INVALID exception when result overflows but exception would not result from cast. * math/libm-test.inc (lround_test_data): Add more tests. (llround_test_data): Likewise.
2015-10-07Fix ldbl-128 lrintl, lroundl missing exceptions for 32-bit long (bug 19085).Joseph Myers1-1/+1
The ldbl-128 implementations of lrintl and lroundl miss "invalid" exceptions on systems with 32-bit long for arguments that overflow long but have exponent below 48. This patch fixes this by rearranging the sequence of tests in the code so the exponent < 48 case is only used for exponents that don't overflow long. Tested for mips64 (n32 and n64). [BZ #19085] * sysdeps/ieee754/ldbl-128/s_lrintl.c (__lrintl): Move test for exponent below 48 inside case for non-overflowing exponent. * sysdeps/ieee754/ldbl-128/s_lroundl.c (__lroundl): Likewise.
2015-10-07Don't use dbl-64/wordsize-64 lround based on llround for ILP32 (bug 19079).Joseph Myers1-1/+1
The implementation of lround in dbl-64/wordsize-64 as an alias or wrapper for llround is always incorrect when long is not 64-bit, because it misses required exceptions in overflow cases, as shown by my recently added tests. This patch removes that alias / wrapper in the non-LP64 case, together with the REGISTER_CAST_INT32_TO_INT64 macro, restoring the previous version of lround for dbl-64/wordsize-64 (newly conditioned on !_LP64). Tested for x86_64, and for mips64 with use of dbl-64/wordsize-64 enabled. [BZ #19079] * sysdeps/ieee754/dbl-64/wordsize-64/s_lround.c: Restore previous file, conditioned on [!_LP64]. * sysdeps/ieee754/dbl-64/wordsize-64/s_llround.c [!_LP64] (__lround): Do not define as function or alias. [!_LP64] (lround): Likewise. [!_LP64] (__lroundl): Likewise. [!_LP64] (lroundl): Likewise. * sysdeps/tile/sysdep.h (REGISTER_CAST_INT32_TO_INT64): Remove macro. * sysdeps/x86_64/x32/sysdep.h (REGISTER_CAST_INT32_TO_INT64): Likewise.
2015-10-06Fix ldbl-128ibm expl overflow in non-default rounding modes (bug 19078).Joseph Myers1-1/+1
The ldbl-128ibm expl wrapper checks the argument to determine when to call __kernel_standard_l, thereby overriding overflowing results from __ieee754_expl that could otherwise (given appropriately patched libgcc) be correct for the rounding mode. This patch changes it to check the result of __ieee754_expl instead, as other versions of this wrapper do. Tested for powerpc. [BZ #19078] * sysdeps/ieee754/ldbl-128ibm/w_expl.c (o_thres): Remove variable. (u_thres): Likewise. (__expl): Determine whether to call __kernel_standard_l based on value of result, not argument.
2015-10-06Fix ldbl-128ibm logl (1) sign of zero result (bug 19077).Joseph Myers1-1/+1
The ldbl-128ibm implementation of logl produces a zero with the wrong sign for logl (1) in FE_DOWNWARD mode. This patch makes it explicitly return 0.0L in that case, as in e.g. the ldbl-128 implementation. Tested for powerpc. [BZ #19077] * sysdeps/ieee754/ldbl-128ibm/e_logl.c (__ieee754_logl): Return 0.0L for argument 1.0L.
2015-10-06Fix ldbl-128ibm log1pl (-1) sign of infinity (bug 19076).Joseph Myers1-1/+1
The ldbl-128ibm implementation of log1pl produces an infinity with the wrong sign for log1pl (-1) in FE_DOWNWARD mode. This patch fixes this by changing a division (-1.0L / (x - x)) (incorrect in FE_DOWNWARD mode) to (-1.0L / 0.0L) (correct in all rounding modes). Tested for powerpc. [BZ #19076] * sysdeps/ieee754/ldbl-128ibm/s_log1pl.c (__log1pl): Divide by constant 0.0L when computing infinite result.
2015-10-06nss_nis: Do not call malloc_usable_size [BZ #10432]Florian Weimer1-10/+10
This is a namespace violation, and interposed malloc implementations are not required to interpose malloc_usable_size.
2015-10-06Harden tls_dtor_list with pointer mangling [BZ #19018]Florian Weimer1-2/+2
2015-10-05Fix BZ #19012 -- iconv_open leaks memory on error path.Paul Pluzhnikov1-2/+2
2015-10-05Fix ldbl-96 lroundl just below powers of 2 (bug 19071).Joseph Myers1-1/+2
The ldbl-96 version of lroundl is incorrect for systems with 64-bit long when the argument's absolute value is just below a power of 2, 2^32 or more, and rounds up to the next integer; in such cases, it returns 0. The problem is incrementing the high part of the mantissa loses the high bit of the value (which is not an issue for any other floating-point format, and is handled specially in lround when the bit corresponding to 0.5 was in the high part rather than the low part). This patch fixes this in a similar way to that used in llroundl: storing the high part in an unsigned long variable before incrementing it, so problems cannot occur in the case when this code is reachable. I improved test coverage for both lround and llround by making them use the same test inputs (appropriately conditioned on the size of long in the lround case) - complete with the same comments, to make comparison as easy as possible. (This test coverage improvement was how I found the lroundl bug.) Tested for x86_64 and x86. [BZ #19071] * sysdeps/ieee754/ldbl-96/s_lroundl.c (__lroundl): Use unsigned long int variable to store possibly incremented high part of mantissa. * math/libm-test.inc (lround_test_data): Add tests used for llround. Use [LONG_MAX > 0x7fffffff] consistently as condition for tests requiring 64-bit long. Do not condition tests on [TEST_FLOAT] unnecessarily. (llround_test_data): Add tests used for lround. Add another expectation for the "inexact" exception. Do not condition tests on [TEST_FLOAT] unnecessarily.
2015-10-05Don't list bug 887 as fixed for glibc 2.16.Joseph Myers1-23/+23
2015-10-05Work around powerpc32 integer 0 converting to -0 (bug 887, bug 19049, bug ↵Joseph Myers1-9/+9
19050). On powerpc32 hard-float, older processors (ones where fcfid is not available for 32-bit code), GCC generates conversions from integers to floating point that wrongly convert integer 0 to -0 instead of +0 in FE_DOWNWARD mode. This in turn results in logb and a few other functions wrongly returning -0 when they should return +0. This patch works around this issue in glibc as I proposed in <https://sourceware.org/ml/libc-alpha/2015-09/msg00728.html>, so that the affected functions can be correct and the affected tests pass in the absence of a GCC fix for this longstanding issue (GCC bug 67771 - if fixed, of course we can put in GCC version conditionals, and eventually phase out the workarounds). A new macro FIX_INT_FP_CONVERT_ZERO is added in a new sysdeps header fix-int-fp-convert-zero.h, and the powerpc32/fpu version of that header defines the macro based on the results of a configure test for whether such conversions use the fcfid instruction. Tested for x86_64 (that installed stripped shared libraries are unchanged by the patch) and powerpc (that HAVE_PPC_FCFID comes out to 0 as expected and that the relevant tests are fixed). Also tested a build with GCC configured for -mcpu=power4 and verified that HAVE_PPC_FCFID comes out to 1 in that case. There are still some other issues to fix to get test-float and test-double passing cleanly for older powerpc32 processors (apart from the need for an ulps regeneration for powerpc). (test-ldouble will be harder to get passing cleanly, but with a combination of selected fixes to ldbl-128ibm code that don't involve significant performance issues, allowing spurious underflow and inexact exceptions for that format, and lots of XFAILing for the default case of unpatched libgcc, it should be doable.) [BZ #887] [BZ #19049] [BZ #19050] * sysdeps/generic/fix-int-fp-convert-zero.h: New file. * sysdeps/ieee754/dbl-64/e_log10.c: Include <fix-int-fp-convert-zero.h>. (__ieee754_log10): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO. * sysdeps/ieee754/dbl-64/e_log2.c: Include <fix-int-fp-convert-zero.h>. (__ieee754_log2): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO. * sysdeps/ieee754/dbl-64/s_erf.c: Include <fix-int-fp-convert-zero.h>. (__erfc): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO. * sysdeps/ieee754/dbl-64/s_logb.c: Include <fix-int-fp-convert-zero.h>. (__logb): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO. * sysdeps/ieee754/flt-32/e_log10f.c: Include <fix-int-fp-convert-zero.h>. (__ieee754_log10f): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO. * sysdeps/ieee754/flt-32/e_log2f.c: Include <fix-int-fp-convert-zero.h>. (__ieee754_log2f): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO. * sysdeps/ieee754/flt-32/s_erff.c: Include <fix-int-fp-convert-zero.h>. (__erfcf): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO. * sysdeps/ieee754/flt-32/s_logbf.c: Include <fix-int-fp-convert-zero.h>. (__logbf): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO. * sysdeps/ieee754/ldbl-128ibm/s_erfl.c: Include <fix-int-fp-convert-zero.h>. (__erfcl): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO. * sysdeps/ieee754/ldbl-128ibm/s_logbl.c: Include <fix-int-fp-convert-zero.h>. (__logbl): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO. * sysdeps/powerpc/powerpc32/fpu/configure.ac: New file. * sysdeps/powerpc/powerpc32/fpu/configure: New generated file. * sysdeps/powerpc/powerpc32/fpu/fix-int-fp-convert-zero.h: New file. * config.h.in [_LIBC] (HAVE_PPC_FCFID): New macro.
2015-10-02Fix nexttoward overflow in non-default rounding modes (bug 19059).Joseph Myers1-1/+1
ISO C requires overflowing results from nexttoward to be the appropriate infinity independent of the rounding mode, but some implementations use a rounding-mode-dependent result (this is the same issue as was fixed for nextafter in bug 16677). This patch fixes the problem by making the nexttoward implementations discard the result from the floating-point computation that forced an overflow exception and then return the infinity previously computed with integer arithmetic. Tested for x86_64, x86, mips64 and powerpc. [BZ #19059] * math/s_nexttowardf.c (__nexttowardf): Do not return value from overflowing computation. * sysdeps/i386/fpu/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/i386/fpu/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-128/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/ieee754/ldbl-128/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-96/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/ieee754/ldbl-96/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c (__nldbl_nexttowardf): Likewise. * math/libm-test.inc (nexttoward_test_data): Add more tests.
2015-10-02Harden putpwent, putgrent, putspent, putspent against injection [BZ #18724]Florian Weimer1-5/+5
This prevents injection of ':' and '\n' into output functions which use the NSS files database syntax. Critical fields (user/group names and file system paths) are checked strictly. For backwards compatibility, the GECOS field is rewritten instead. The getent program is adjusted to use the put*ent functions in libc, instead of local copies. This changes the behavior of getent if user names start with '-' or '+'.
2015-10-01Fix ldbl-128 / ldbl-128ibm lgamma overflow handling (bug 16347, bug 19046).Joseph Myers1-8/+8
The ldbl-128 / ldbl-128ibm implementation of lgamma has problems with its handling of large arguments. It has an overflow threshold that is correct only for ldbl-128, despite being used for both types - with diagnostic control macros as a temporary measure to disable warnings about that constant overflowing for ldbl-128ibm - and it has a calculation that's roughly x * log(x) - x, resulting in overflows for arguments that are roughly at most a factor 1/log(threshold) below the overflow threshold. This patch fixes both issues, using an overflow threshold appropriate for the type in question and adding another case for large arguments that avoids the possible intermediate overflow. Tested for x86_64, x86, mips64 and powerpc. [BZ #16347] [BZ #19046] * sysdeps/ieee754/ldbl-128/e_lgammal_r.c: Do not include <libc-internal.h>. (MAXLGM): Do not use diagnostic control macros. [LDBL_MANT_DIG == 106] (MAXLGM): Change value to overflow threshold for ldbl-128ibm. (__ieee754_lgammal_r): For large arguments, multiply by log - 1 instead of multiplying by log then subtracting. * math/auto-libm-test-in: Add more tests of lgamma. * math/auto-libm-test-out: Regenerated.
2015-09-30Fix ldbl-128ibm exp10l spurious overflows (bug 16620).Joseph Myers1-8/+8
The ldbl-128ibm implementation of exp10l uses a version of log(10) split into high and low parts - but the low part is negative, so causing spurious overflows from __ieee754_expl (exp_high) in cases close to the overflow threshold (I added relevant tests close to the overflow threshold to the testsuite earlier today). The same issue applies close to the underflow threshold as well (except that spurious underflows in IBM long double arithmetic are harder to fix than the other deficiencies, so we might end up permitting those for IBM long double in the libm testsuite, as permitted by ISO C). This patch fixes it to use a low part rounded downward to 48 bits instead. (The choice of 48 instead of 53 bits is to make it more obviously safe even when the low part of the argument is negative.) Tested for powerpc. (Note that because of libgcc bugs with multiplication very close to LDBL_MAX, libgcc also needs patching for all the problem cases to be fixed, but this patch is still safe and correct in the absence of such libgcc fixes.) [BZ #16620] * sysdeps/ieee754/ldbl-128ibm/e_exp10l.c (log10_high): Use value of log (10) rounded downward to 48 bits. (log10_low): Use corresponding low part of log (10).
2015-09-30Fix i386 acosh (-qNaN) spurious "invalid" exception.Joseph Myers1-1/+1
The i386 versions of acoshf and acosh raise a spurious "invalid" exception for an argument that is a quiet NaN with the sign bit set. The integer arithmetic to detect arguments < 1 also detects -NaN, and then the computation 0 / 0 in that case raises the exception. This patch fixes this by using (x - x) / (x - x) as the computation in that case instead, which will always raise the exception for non-NaN arguments reaching that code, but not for quiet NaN arguments. Tested for x86_64 and x86. [BZ #19032] * sysdeps/i386/fpu/e_acosh.S (__ieee754_acosh): For arguments < 1, compute result as (x - x) / (x - x) not as 0 / 0. * sysdeps/i386/fpu/e_acoshf.S (__ieee754_acoshf): Likewise. * math/libm-test.inc (acosh_test_data): Add another test of acosh.
2015-09-28Fix clog, clog10 inaccuracy (bug 19016).Joseph Myers1-1/+2
For arguments with X^2 + Y^2 close to 1, clog and clog10 avoid large errors from log(hypot) by computing X^2 + Y^2 - 1 in a way that avoids cancellation error and then using log1p. However, the thresholds for using that approach still result in log being used on argument as large as sqrt(13/16) > 0.9, leading to significant errors, in some cases above the 9ulp maximum allowed in glibc libm. This patch arranges for the approach using log1p to be used in any cases where |X|, |Y| < 1 and X^2 + Y^2 >= 0.5 (with the existing allowance for cases where one of X and Y is very small), adjusting the __x2y2m1 functions to work with the wider range of inputs. This way, log only gets used on arguments below sqrt(1/2) (or substantially above 1), where the error involved is much less. Tested for x86_64, x86, mips64 and powerpc. For the ulps regeneration I removed the existing clog and clog10 ulps before regenerating to allow any reduced ulps to appear. Tests added include those found by random test generation to produce large ulps either before or after the patch, and some found by trying inputs close to the (0.75, 0.5) threshold where the potential errors from using log are largest. [BZ #19016] * sysdeps/generic/math_private.h (__x2y2m1f): Update comment to allow more cases with X^2 + Y^2 >= 0.5. * sysdeps/ieee754/dbl-64/x2y2m1.c (__x2y2m1): Likewise. Add -1 as normal element in sum instead of special-casing based on values of arguments. * sysdeps/ieee754/dbl-64/x2y2m1f.c (__x2y2m1f): Update comment. * sysdeps/ieee754/ldbl-128/x2y2m1l.c (__x2y2m1l): Likewise. Add -1 as normal element in sum instead of special-casing based on values of arguments. * sysdeps/ieee754/ldbl-128ibm/x2y2m1l.c (__x2y2m1l): Likewise. * sysdeps/ieee754/ldbl-96/x2y2m1.c [FLT_EVAL_METHOD != 0] (__x2y2m1): Update comment. * sysdeps/ieee754/ldbl-96/x2y2m1l.c (__x2y2m1l): Likewise. Add -1 as normal element in sum instead of special-casing based on values of arguments. * math/s_clog.c (__clog): Handle more cases using log1p without hypot. * math/s_clog10.c (__clog10): Likewise. * math/s_clog10f.c (__clog10f): Likewise. * math/s_clog10l.c (__clog10l): Likewise. * math/s_clogf.c (__clogf): Likewise. * math/s_clogl.c (__clogl): Likewise. * math/auto-libm-test-in: Add more tests of clog and clog10. * math/auto-libm-test-out: Regenerated. * sysdeps/i386/fpu/libm-test-ulps: Update. * sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
2015-09-28Let 'make check subdirs=string' succeed even when it's invokedMartin Sebor1-1/+1
immediately after glibc has been built and before 'make check' (or after 'make clean').
2015-09-26Fix BZ #18985 -- out of range data to strftime() causes a segfaultPaul Pluzhnikov1-1/+1
2015-09-26Fix powf inaccuracy (bug 18956).Joseph Myers1-2/+2
The flt-32 version of powf can be inaccurate because of bugs in the extra-precision calculation of (x-1)/(x+1) or (x-1.5)/(x+1.5) as part of calculating log(x) with extra precision: a constant used (as part of adding 1 or 1.5 through integer arithmetic) is incorrect, and then the code fails to mask a computed high part before using it in arithmetic that relies on s_h*t_h being exactly representable. This patch fixes these bugs. Tested for x86_64 and x86. x86_64 ulps for powf removed and regenerated to reflect reduced ulps from the increased accuracy for existing tests. [BZ #18956] * sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Add 0x00400000 not 0x0040000 for high bit of mantissa. Mask with 0xfffff000 when extracting high part. * math/auto-libm-test-in: Add another test of pow. * math/auto-libm-test-out: Regenerated. * sysdeps/x86_64/fpu/libm-test-ulps: Update.
2015-09-25Fix pow missing underflows (bug 18825).Joseph Myers1-3/+3
Similar to various other bugs in this area, pow functions can fail to raise the underflow exception when the result is tiny and inexact but one or more low bits of the intermediate result that is scaled down (or, in the i386 case, converted from a wider evaluation format) are zero. This patch forces the exception in a similar way to previous fixes, thereby concluding the fixes for known bugs with missing underflow exceptions currently filed in Bugzilla. Tested for x86_64, x86, mips64 and powerpc. [BZ #18825] * sysdeps/i386/fpu/i386-math-asm.h (FLT_NARROW_EVAL_UFLOW_NONNAN): New macro. (DBL_NARROW_EVAL_UFLOW_NONNAN): Likewise. (LDBL_CHECK_FORCE_UFLOW_NONNAN): Likewise. * sysdeps/i386/fpu/e_pow.S: Use DEFINE_DBL_MIN. (__ieee754_pow): Use DBL_NARROW_EVAL_UFLOW_NONNAN instead of DBL_NARROW_EVAL, reloading the PIC register as needed. * sysdeps/i386/fpu/e_powf.S: Use DEFINE_FLT_MIN. (__ieee754_powf): Use FLT_NARROW_EVAL_UFLOW_NONNAN instead of FLT_NARROW_EVAL. Use separate return path for case when first argument is NaN. * sysdeps/i386/fpu/e_powl.S: Include <i386-math-asm.h>. Use DEFINE_LDBL_MIN. (__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN, reloading the PIC register. * sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Use math_check_force_underflow_nonneg. * sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Force underflow for subnormal result. * sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Use math_check_force_underflow_nonneg. * sysdeps/x86/fpu/powl_helper.c (__powl_helper): Use math_check_force_underflow. * sysdeps/x86_64/fpu/x86_64-math-asm.h (LDBL_CHECK_FORCE_UFLOW_NONNAN): New macro. * sysdeps/x86_64/fpu/e_powl.S: Include <x86_64-math-asm.h>. Use DEFINE_LDBL_MIN. (__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN. * math/auto-libm-test-in: Add more tests of pow. * math/auto-libm-test-out: Regenerated.
2015-09-25[BZ #17250] Fix static dlopen default library search pathMaciej W. Rozycki1-6/+6
Fix a regression introduced with commit 0d23a5c1 [Static dlopen correction fallout fixes] that caused the default library search path to be ignored for modules loaded with dlopen from static executables. [BZ #17250] * elf/dl-support.c (_dl_main_map): Don't initialize l_flags_1 member.
2015-09-24Fix hypot missing underflows (bug 18803).Joseph Myers1-3/+3
Similar to various other bugs in this area, hypot functions can fail to raise the underflow exception when the result is tiny and inexact but one or more low bits of the intermediate result that is scaled down (or, in the i386 case, converted from a wider evaluation format) are zero. This patch forces the exception in a similar way to previous fixes. Note that this issue cannot arise for implementations of hypotf using double (or wider) for intermediate evaluation (if hypotf should underflow, that means the double square root is being computed of some number of the form N*2^-298, for 0 < N < 2^46, which is exactly represented as a double, and whatever the rounding mode such a square root cannot have a mantissa with all zeroes after the initial 23 bits). Thus no changes are made to hypotf implementations in this patch, only to hypot and hypotl. Tested for x86_64, x86, mips64 and powerpc. [BZ #18803] * sysdeps/i386/fpu/e_hypot.S: Use DEFINE_DBL_MIN. (MO): New macro. (__ieee754_hypot) [PIC]: Load PIC register. (__ieee754_hypot): Use DBL_NARROW_EVAL_UFLOW_NONNEG instead of DBL_NARROW_EVAL. * sysdeps/ieee754/dbl-64/e_hypot.c (__ieee754_hypot): Use math_check_force_underflow_nonneg in case where result might be tiny. * sysdeps/ieee754/ldbl-128/e_hypotl.c (__ieee754_hypotl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_hypotl.c (__ieee754_hypotl): Likewise. * sysdeps/ieee754/ldbl-96/e_hypotl.c (__ieee754_hypotl): Likewise. * sysdeps/powerpc/fpu/e_hypot.c (__ieee754_hypot): Likewise. * math/auto-libm-test-in: Add more tests of hypot. * math/auto-libm-test-out: Regenerated.
2015-09-24Fix x86_64 fma4 pow inappropriate contraction (bug 19003).Joseph Myers1-1/+1
The x86_64 fma4 version of pow fails to disable contraction of operations other than those explicitly intended to use fma instructions, so resulting in large ulps errors on processors with fma4 instructions, as in bug 18104 (165ulp for the test added for that bug; error originally reported by "blaaa" on #glibc). This patch adds $(config-cflags-nofma) for e_pow-fma4.c, corresponding to the use for e_pow.c in sysdeps/ieee754/dbl-64/Makefile. Tested for x86_64 on a processor with fma4. [BZ #19003] * sysdeps/x86_64/fpu/multiarch/Makefile (CFLAGS-e_pow-fma4.c): Add $(config-cflags-nofma).