Global USE flags

Flag	Description	Packages
debug		2
qt5	GUI using Qt5 lib	2
static-libs	Build static libs	2

Local USE flags

dev-libs

xml-security-c

Flag	Description
examples
nss	Use <pkg>dev-libs/nss</pkg> for certain crypto operations (configureable at runtime)
xalan	Enable support for XSLT and XPath parsing by <pkg>dev-libs/xalan-c</pkg>

media-gfx

ktikz

Flag	Description
doc
kde

media-video

calyp

Flag	Description
cpu_flags_x86_sse
ffmpeg	Support ffmpeg formats
opencv	Support for opencv
qt4	GUI using Qt4 lib

net-im

yakyak-bin

Flag	Description
gnome

x11-misc

barrier

Flag	Description
libressl

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