From e134ca175318e0f1c04b4e857f38efae091c35ce Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Tue, 9 Jan 2018 22:34:35 +0000 Subject: Fix powerpc-nofpu complex long double functions spurious "invalid" exception (bug 22687). For soft-float powerpc, various _Complex long double functions generate spurious "invalid" exceptions, even with a compiler with GCC bug 64811 fixed. The problem is GCC's built-in fabsl expansion. Various files are already built with -fno-builtin-fabsl because in this case (IBM long double, for soft-float or e500v1) a fallback fabsl expansion based on comparisons is used, which can produce the wrong sign of a zero result. Those comparisons can also produce spurious exceptions for NaN arguments. Furthermore, __builtin_fpclassify implemently uses __builtin_fabsl, and is unaffected by -fno-builtin-fabsl, and the fpclassify macro uses __builtin_fpclassify in the absence of -fsignaling-nans. Thus, this patch arranges for the problem files using fpclassify to be built with -fsignaling-nans in this case, to avoid spurious exceptions from fpclassify. Tested for powerpc (soft-float). [BZ #22687] * sysdeps/powerpc/nofpu/Makefile (CFLAGS-s_cacosl.c): New variable. (CFLAGS-s_cacoshl.c): Likewise. (CFLAGS-s_casinhl.c): Likewise. (CFLAGS-s_catanl.c): Likewise. (CFLAGS-s_catanhl.c): Likewise. (CFLAGS-s_cexpl.c): Likewise. (CFLAGS-s_ccoshl.c): Add -fsignaling-nans. (CFLAGS-s_csinhl.c): Likewise. (CFLAGS-s_clogl.c): Likewise. (CFLAGS-s_clog10l.c): Likewise. (CFLAGS-s_csinl.c): Likewise. (CFLAGS-s_csqrtl.c): Likewise. --- sysdeps/powerpc/nofpu/Makefile | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) (limited to 'sysdeps') diff --git a/sysdeps/powerpc/nofpu/Makefile b/sysdeps/powerpc/nofpu/Makefile index ed16321..09ecdf1 100644 --- a/sysdeps/powerpc/nofpu/Makefile +++ b/sysdeps/powerpc/nofpu/Makefile @@ -15,15 +15,29 @@ CPPFLAGS += -I../soft-fp/ # gcc-4.1.1 and may be too late for gcc-4.2. So we need these flags # until the fix in a gcc release and glibc drops support for earlier # versions of gcc. +# +# This bug can cause wrong signs of zero results from fabsl, and +# spurious "invalid" exceptions from comparisons with NaN in the +# default code sequence generated. The fpclassify expansion used by +# __builtin_fpclassify, which is used in the absence of +# -fsignaling-nans, uses __builtin_fabsl, and is not affected by +# -fno-builtin-fabsl, so requiring -fsignaling-nans for some affected +# source files. CFLAGS-e_atan2l.c += -fno-builtin-fabsl CFLAGS-e_hypotl.c += -fno-builtin-fabsl CFLAGS-e_powl.c += -fno-builtin-fabsl -CFLAGS-s_ccoshl.c += -fno-builtin-fabsl -CFLAGS-s_csinhl.c += -fno-builtin-fabsl -CFLAGS-s_clogl.c += -fno-builtin-fabsl -CFLAGS-s_clog10l.c += -fno-builtin-fabsl -CFLAGS-s_csinl.c += -fno-builtin-fabsl -CFLAGS-s_csqrtl.c += -fno-builtin-fabsl +CFLAGS-s_cacosl.c += -fsignaling-nans +CFLAGS-s_cacoshl.c += -fsignaling-nans +CFLAGS-s_casinhl.c += -fsignaling-nans +CFLAGS-s_catanl.c += -fsignaling-nans +CFLAGS-s_catanhl.c += -fsignaling-nans +CFLAGS-s_ccoshl.c += -fno-builtin-fabsl -fsignaling-nans +CFLAGS-s_cexpl.c += -fsignaling-nans +CFLAGS-s_csinhl.c += -fno-builtin-fabsl -fsignaling-nans +CFLAGS-s_clogl.c += -fno-builtin-fabsl -fsignaling-nans +CFLAGS-s_clog10l.c += -fno-builtin-fabsl -fsignaling-nans +CFLAGS-s_csinl.c += -fno-builtin-fabsl -fsignaling-nans +CFLAGS-s_csqrtl.c += -fno-builtin-fabsl -fsignaling-nans CFLAGS-w_acosl_compat.c += -fno-builtin-fabsl CFLAGS-w_asinl_compat.c += -fno-builtin-fabsl CFLAGS-w_atanhl_compat.c += -fno-builtin-fabsl -- cgit v1.1