From: Gabriel F. T. Gomes Date: Fri, 3 Nov 2017 12:44:36 +0000 (-0200) Subject: Provide a C++ version of iseqsig (bug 22377) X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=38e08dc3e00fc27d127701175018cac4ddaf998e;p=thirdparty%2Fglibc.git Provide a C++ version of iseqsig (bug 22377) In C++ mode, __MATH_TG cannot be used for defining iseqsig, because __MATH_TG relies on __builtin_types_compatible_p, which is a C-only builtin. This is true when float128 is provided as an ABI-distinct type from long double. Moreover, the comparison macros from ISO C take two floating-point arguments, which need not have the same type. Choosing what underlying function to call requires evaluating the formats of the arguments, then selecting which is wider. The macro __MATH_EVAL_FMT2 provides this information, however, only the type of the macro expansion is relevant (actually evaluating the expression would be incorrect). This patch provides a C++ version of iseqsig, in which only the type of __MATH_EVAL_FMT2 (__typeof or decltype) is used as a template parameter for __iseqsig_type. This function calls the appropriate underlying function. Tested for powerpc64le and x86_64. [BZ #22377] * math/Makefile [C++] (tests): Add test for iseqsig. * math/math.h [C++] (iseqsig): New implementation, which does not rely on __MATH_TG/__builtin_types_compatible_p. * math/test-math-iseqsig.cc: New file. * sysdeps/powerpc/powerpc64le/Makefile (CFLAGS-test-math-iseqsig.cc): New variable. (cherry picked from commit c85e54ac6cef0faed7b7ffc722f52523dec59bf5) --- diff --git a/ChangeLog b/ChangeLog index 9f65a5cca1f..6b4d908253f 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,13 @@ +2017-12-19 Gabriel F. T. Gomes + + [BZ #22377] + * math/Makefile [C++] (tests): Add test for iseqsig. + * math/math.h [C++] (iseqsig): New implementation, which does + not rely on __MATH_TG/__builtin_types_compatible_p. + * math/test-math-iseqsig.cc: New file. + * sysdeps/powerpc/powerpc64le/Makefile + (CFLAGS-test-math-iseqsig.cc): New variable. + 2017-10-18 Renlin Li * sysdeps/aarch64/dl-machine.h (elf_machine_load_address): Use diff --git a/NEWS b/NEWS index d4af1653f20..00945ced729 100644 --- a/NEWS +++ b/NEWS @@ -100,6 +100,7 @@ The following bugs are resolved with this release: [22322] libc: [mips64] wrong bits/long-double.h installed [22325] glibc: Memory leak in glob with GLOB_TILDE (CVE-2017-15671) [22375] malloc returns pointer from tcache instead of NULL (CVE-2017-17426) + [22377] Provide a C++ version of iseqsig [22636] PTHREAD_STACK_MIN is too small on x86-64 [22627] $ORIGIN in $LD_LIBRARY_PATH is substituted twice [22637] nptl: Fix stack guard size accounting diff --git a/math/Makefile b/math/Makefile index 2c17c68eda7..1039985ea6b 100644 --- a/math/Makefile +++ b/math/Makefile @@ -204,7 +204,7 @@ tests-static = test-fpucw-static test-fpucw-ieee-static \ ifneq (,$(CXX)) tests += test-math-isinff test-math-iszero test-math-issignaling \ - test-math-iscanonical + test-math-iscanonical test-math-iseqsig endif ifneq (no,$(PERL)) diff --git a/math/math.h b/math/math.h index ba266248353..5a282b8c6b6 100644 --- a/math/math.h +++ b/math/math.h @@ -845,8 +845,76 @@ extern int matherr (struct exception *__exc); /* Return X == Y but raising "invalid" and setting errno if X or Y is a NaN. */ -# define iseqsig(x, y) \ - __MATH_TG (__MATH_EVAL_FMT2 (x, y), __iseqsig, ((x), (y))) +# if !defined __cplusplus || (__cplusplus < 201103L && !defined __GNUC__) +# define iseqsig(x, y) \ + __MATH_TG (__MATH_EVAL_FMT2 (x, y), __iseqsig, ((x), (y))) +# else +/* In C++ mode, __MATH_TG cannot be used, because it relies on + __builtin_types_compatible_p, which is a C-only builtin. Moreover, + the comparison macros from ISO C take two floating-point arguments, + which need not have the same type. Choosing what underlying function + to call requires evaluating the formats of the arguments, then + selecting which is wider. The macro __MATH_EVAL_FMT2 provides this + information, however, only the type of the macro expansion is + relevant (actually evaluating the expression would be incorrect). + Thus, the type is used as a template parameter for __iseqsig_type, + which calls the appropriate underlying function. */ +extern "C++" { +template struct __iseqsig_type; + +template<> struct __iseqsig_type +{ + static int __call (float __x, float __y) throw () + { + return __iseqsigf (__x, __y); + } +}; + +template<> struct __iseqsig_type +{ + static int __call (double __x, double __y) throw () + { + return __iseqsig (__x, __y); + } +}; + +template<> struct __iseqsig_type +{ + static int __call (double __x, double __y) throw () + { +# ifndef __NO_LONG_DOUBLE_MATH + return __iseqsigl (__x, __y); +# else + return __iseqsig (__x, __y); +# endif + } +}; + +# if __HAVE_DISTINCT_FLOAT128 +template<> struct __iseqsig_type<_Float128> +{ + static int __call (_Float128 __x, _Float128 __y) throw () + { + return __iseqsigf128 (__x, __y); + } +}; +# endif + +template +inline int +iseqsig (_T1 __x, _T2 __y) throw () +{ +# if __cplusplus >= 201103L + typedef decltype (__MATH_EVAL_FMT2 (__x, __y)) _T3; +# else + typedef __typeof (__MATH_EVAL_FMT2 (__x, __y)) _T3; +# endif + return __iseqsig_type<_T3>::__call (__x, __y); +} + +} /* extern "C++" */ +# endif /* __cplusplus */ + #endif __END_DECLS diff --git a/math/test-math-iseqsig.cc b/math/test-math-iseqsig.cc new file mode 100644 index 00000000000..48e8f1e7994 --- /dev/null +++ b/math/test-math-iseqsig.cc @@ -0,0 +1,111 @@ +/* Test for the C++ implementation of iseqsig. + Copyright (C) 2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#define _GNU_SOURCE 1 +#include +#include + +#include + +/* There is no NaN for _Float128 in std::numeric_limits. + Include ieee754_float128.h and use the bitfields in the union + ieee854_float128.ieee_nan to build a NaN. */ +#if __HAVE_DISTINCT_FLOAT128 +# include +#endif + +#include + +static void +check (int actual, int expected, const char *actual_expr, int line) +{ + if (actual != expected) + { + support_record_failure (); + printf ("%s:%d: error: %s\n", __FILE__, line, actual_expr); + printf ("%s:%d: expected: %d\n", __FILE__, line, expected); + printf ("%s:%d: actual: %d\n", __FILE__, line, actual); + } +} + +#define CHECK(actual, expected) \ + check ((actual), (expected), #actual, __LINE__) + +template +static void +check_type () +{ + T1 t1 = 0; + T2 t2 = 0; + CHECK (iseqsig (t1, t2), 1); + + t2 = 1; + CHECK (iseqsig (t1, t2), 0); + + if (std::numeric_limits::has_quiet_NaN + && std::numeric_limits::has_quiet_NaN) + { + CHECK (iseqsig (std::numeric_limits::quiet_NaN (), t2), 0); + CHECK (iseqsig (t1, std::numeric_limits::quiet_NaN ()), 0); + CHECK (iseqsig (std::numeric_limits::quiet_NaN (), + std::numeric_limits::quiet_NaN ()), 0); + } +} + +#if __HAVE_DISTINCT_FLOAT128 +static void +check_float128 () +{ + ieee854_float128 q1, q2, q3_nan; + + q1.d = 0; + q2.d = 1; + q3_nan.ieee_nan.negative = 0; + q3_nan.ieee_nan.exponent = 0x7FFF; + q3_nan.ieee_nan.quiet_nan = 1; + q3_nan.ieee_nan.mantissa0 = 0x0000; + q3_nan.ieee_nan.mantissa1 = 0x00000000; + q3_nan.ieee_nan.mantissa2 = 0x00000000; + q3_nan.ieee_nan.mantissa3 = 0x00000000; + + CHECK (iseqsig (q1.d, q1.d), 1); + CHECK (iseqsig (q1.d, q2.d), 0); + CHECK (iseqsig (q1.d, q3_nan.d), 0); + CHECK (iseqsig (q3_nan.d, q3_nan.d), 0); +} +#endif + +static int +do_test (void) +{ + check_type (); + check_type (); + check_type (); + check_type (); + check_type (); + check_type (); + check_type (); + check_type (); + check_type (); +#if __HAVE_DISTINCT_FLOAT128 + check_float128 (); +#endif + return 0; +} + +#include diff --git a/sysdeps/powerpc/powerpc64le/Makefile b/sysdeps/powerpc/powerpc64le/Makefile index f554a791b77..7f83a19b9aa 100644 --- a/sysdeps/powerpc/powerpc64le/Makefile +++ b/sysdeps/powerpc/powerpc64le/Makefile @@ -17,9 +17,14 @@ $(foreach suf,$(all-object-suffixes),$(objpfx)test-float128%$(suf)): CFLAGS += - $(foreach suf,$(all-object-suffixes),$(objpfx)test-ifloat128%$(suf)): CFLAGS += -mfloat128 CFLAGS-libm-test-support-float128.c += -mfloat128 CFLAGS-test-math-iscanonical.cc += -mfloat128 +CFLAGS-test-math-iseqsig.cc += -mfloat128 CFLAGS-test-math-issignaling.cc += -mfloat128 CFLAGS-test-math-iszero.cc += -mfloat128 -$(objpfx)test-float128% $(objpfx)test-ifloat128% $(objpfx)test-math-iszero: \ +$(foreach test, \ + test-float128% test-ifloat128% \ + test-math-iscanonical test-math-iseqsig test-math-issignaling \ + test-math-iszero, \ + $(objpfx)$(test)): \ gnulib-tests += $(f128-loader-link) endif