Ping patch. https://gcc.gnu.org/pipermail/gcc-patches/2022-January/588292.html
| Date: Wed, 12 Jan 2022 13:04:19 -0500 | From: Michael Meissner <meiss...@linux.ibm.com> | Subject: [PATCH] Use system default for long double if not specified on PowerPC. | Message-ID: <yd8yi+xecc2yl...@toto.the-meissners.org> I believe this patch will be very important when Linux distributions start moving to using IEEE 128-bit floating point format. Note, the patch was made before changing the .c files to .cc. Here is the patch after the renaming. [PATCH] Use system default for long double if not specified on PowerPC. If the user did not specify a default long double format, use the long double default for the build compiler for the long double default. This patch will allow compilers built on a distribution that has changed the 128-bit floating point format to use the default used on the system. I did a normal normal bootstrap and make check regression on a little endian power9 system and there were no regressions. In addition, I built a compiler where I configured the default to use IEEE 128-bit floating point for long double. I then used that compiler to build a bootstrap with this patch applied and I did not set the floating point format. I verified that the compiler built with this patch defaults long double to be IEEE 128-bit. Can I apply this patch to the trunk for GCC 12? gcc/ 2022-01-20 Michael Meissner <meiss...@the-meissners.org> * config/rs6000/rs6000.cc (TARGET_IEEEQUAD_DEFAULT): If the compiler used to build the current compiler defaults to IEEE 128-bit long double, make that the default for this build. --- gcc/config/rs6000/rs6000.cc | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc index 81a4ede0e8e..0a9d62b3dfd 100644 --- a/gcc/config/rs6000/rs6000.cc +++ b/gcc/config/rs6000/rs6000.cc @@ -91,14 +91,22 @@ explicitly redefine TARGET_IEEEQUAD and TARGET_IEEEQUAD_DEFAULT to 0, so those systems will not pick up this default. This needs to be after all of the include files, so that POWERPC_LINUX and POWERPC_FREEBSD are - properly defined. */ + properly defined. + + If we are being built by a compiler that uses IEEE 128-bit as the default + long double and no explicit long double format was selected, then also + default long double to IEEE 128-bit. */ #ifndef TARGET_IEEEQUAD_DEFAULT #if !defined (POWERPC_LINUX) && !defined (POWERPC_FREEBSD) #define TARGET_IEEEQUAD_DEFAULT 1 #else +#ifdef __LONG_DOUBLE_IEEE128__ +#define TARGET_IEEEQUAD_DEFAULT 1 +#else #define TARGET_IEEEQUAD_DEFAULT 0 #endif #endif +#endif /* Don't enable PC-relative addressing if the target does not support it. */ #ifndef PCREL_SUPPORTED_BY_OS -- Michael Meissner, IBM PO Box 98, Ayer, Massachusetts, USA, 01432 email: meiss...@linux.ibm.com