dev-libs/gmp: drop USE=pgo from stable ebuild, bug #658688

USE=pgo generates optimal constants when running 'tuneup' benchmark
locally. If benchmark does not succeed default parameters are used.
Else benchmark's output is used to tune gmp behaviour.

Unfortunately at least on x86 some primitives like
__mpn_sqr_basecase generate invalid assembly code at fail tests.

In bug #650558 we found out that 'tuneup' is not very well maintained
upstream. Let's dropp support for USE=pgo until it gets better.

Reported-by: Robert Gill
Closes: https://bugs.gentoo.org/658688
Bug: https://bugs.gentoo.org/650558
Package-Manager: Portage-2.3.59, Repoman-2.3.12
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>

dev-libs/gmp/gmp-6.1.2.ebuild

@@ -19,7 +19,7 @@ LICENSE="|| ( LGPL-3+ GPL-2+ )"
 # The subslot reflects the C & C++ SONAMEs.
 SLOT="0/10.4"
 KEYWORDS="alpha amd64 arm arm64 hppa ia64 m68k ~mips ppc ppc64 s390 sh sparc x86 ~ppc-aix ~x64-cygwin ~amd64-fbsd ~x86-fbsd ~amd64-linux ~x86-linux ~ppc-macos ~x64-macos ~x86-macos ~m68k-mint ~sparc-solaris ~sparc64-solaris ~x64-solaris ~x86-solaris"
-IUSE="+asm doc cxx pgo static-libs"
+IUSE="+asm doc cxx static-libs"
 
 DEPEND="sys-devel/m4
 	app-arch/xz-utils"
@@ -87,17 +87,6 @@ multilib_src_configure() {
 
 multilib_src_compile() {
 	emake
-
-	if use pgo ; then
-		emake -j1 -C tune tuneup
-		ebegin "Trying to generate tuned data"
-		./tune/tuneup | tee gmp.mparam.h.new
-		if eend $(( 0 + ${PIPESTATUS[*]/#/+} )) ; then
-			mv gmp.mparam.h.new gmp-mparam.h || die
-			emake clean
-			emake
-		fi
-	fi
 }
 
 multilib_src_test() {

dev-libs/gmp/metadata.xml

@@ -7,6 +7,5 @@
 </maintainer>
 <use>
 	<flag name="asm">Enable use of hand optimized assembly routines (faster execution)</flag>
-	<flag name="pgo">After building gmp, run some tests against to produce faster libraries -- this option will double the compile time</flag>
 </use>
 </pkgmetadata>