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Re: [PATCH v3 05/11] ldbl-128ibm-compat: Add *cvt functions




On 12/3/19 11:05 AM, Gabriel F. T. Gomes wrote:
From: "Gabriel F. T. Gomes" <gabrielftg@linux.ibm.com>

Changes since v2:

   - Fix http URLs.

No changes since v1.

-- 8< --
This patch adds IEEE long double versions of q*cvt* functions for
powerpc64le.  Unlike all other long double to/from string conversion
functions, these do not rely on internal functions that can take
floating-point numbers with different formats and act on them
accordingly, instead, the related files are rebuilt with the
-mabi=ieeelongdouble compiler flag set.

Having -mabi=ieeelongdouble passed to the compiler causes the object
files to be marked with a .gnu_attribute that is incompatible with the
.gnu_attribute in files built with -mabi=ibmlongdouble (the default).
The difference causes error messages similar to the following:

   ld: libc_pic.a(s_isinfl.os) uses IBM long double,
       libc_pic.a(ieee128-qefgcvt_r.os) uses IEEE long double.
   collect2: error: ld returned 1 exit status
   make[2]: *** [../Makerules:649: libc_pic.os] Error 1

Although this warning is useful in other situations, the library
actually needs to have functions with different long double formats, so
.gnu_attribute generation is explicitly disabled for these files with
the use of -mno-gnu-attribute.

Tested for powerpc64le on the branch that actually enables the
sysdeps/ieee754/ldbl-128ibm-compat for powerpc64le.

diff --git a/sysdeps/ieee754/ldbl-128ibm-compat/Makefile b/sysdeps/ieee754/ldbl-128ibm-compat/Makefile
index 6d5414c54a..49d9af9fea 100644
--- a/sysdeps/ieee754/ldbl-128ibm-compat/Makefile
+++ b/sysdeps/ieee754/ldbl-128ibm-compat/Makefile

...

+tests-internal += tst-ibm128-efgcvt tst-ieee128-efgcvt

Are these tests generated? I don't see tst-{ibm128,ieee128}-efgcvt.c in this patch. The patch looks otherwise OK to me.


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