Created attachment 811984 [details]
libcaca_lto_missdetection.tgz

LTO: libcaca build failure as missdetection "HAVE_FLDLN2" & HAVE_FSIN_FCOS

as per comparison of config.status when ppc64le building with and without lto.
(related config* files in attached libcaca_lto_missdetection.tgz)
===
$diff -u libcaca_lto_missdetection/wolto/config.status
libcaca_lto_missdetection/wlto/config.status |grep -B2 ^\+ |tail -n10
--
-"k-clash-protection  -g -I../caca/ -g -O2 -fno-strength-reduce
-fomit-frame-pointer -Wall -Wpointer-arith -Wcast-align -Wcast-qual
-Wstrict-prototype"\
-"s -Wshadow -Waggregate-return -Wmissing-prototypes -Wnested-externs
-Wsign-compare"
+"k-clash-protection -flto=16 -g -I../caca/ -g -O2 -fno-strength-reduce
-fomit-frame-pointer -Wall -Wpointer-arith -Wcast-align -Wcast-qual
-Wstrict-p"\
+"rototypes -Wshadow -Waggregate-return -Wmissing-prototypes -Wnested-externs
-Wsign-compare"
--
 D["HAVE_GETOPT_LONG"]=" 1"
 D["HAVE_GETOPT_LONG"]=" 1"
+D["HAVE_FSIN_FCOS"]=" 1"
+D["HAVE_FLDLN2"]=" 1"
===

related configure.ac lines are:
===
AC_MSG_CHECKING(for fsin/fcos)
AC_TRY_COMPILE([],[double x; asm volatile("fsin; fcos":"=t"(x):);],
 [AC_MSG_RESULT(yes)
  AC_DEFINE(HAVE_FSIN_FCOS, 1, [Define to 1 if you have the ���fsin��� and ���fcos���
instructions.])],
 [AC_MSG_RESULT(no)])

AC_MSG_CHECKING(for fldln2/fxch/fyl2x)
AC_TRY_COMPILE([],[double x; asm volatile("fldln2; fldln2; fxch;
fyl2x":"=t"(x):);],
 [AC_MSG_RESULT(yes)
  AC_DEFINE(HAVE_FLDLN2, 1, [Define to 1 if you have the ���fldln2��� and other
floating point instructions.])],
 [AC_MSG_RESULT(no)])
===

original failure detected in
https://build.opensuse.org/package/show/multimedia:libs/libcaca