Description:
When flag --enable-lto is enabled, compilation fails. 

Steps to Reproduce:
Configure with LTO.


Actual Results:  
Failed compilation:
/var/tmp/portage-ondisk/portage/app-office/libreoffice-5.3.3.2/temp/ccKfBKCF.ltrans20.ltrans.o: In function `MultiLineEdit::~MultiLineEdit()':
<artificial>:(.text+0x213): undefined reference to `vtable for MultiLineEdit'
<artificial>:(.text+0x239): undefined reference to `VTT for MultiLineEdit'
/var/tmp/portage-ondisk/portage/app-office/libreoffice-5.3.3.2/temp/ccKfBKCF.ltrans20.ltrans.o: In function `dp_gui::LicenseView::~LicenseView()':
<artificial>:(.text+0x2fb): undefined reference to `vtable for MultiLineEdit'
<artificial>:(.text+0x332): undefined reference to `vtable for MultiLineEdit'
/var/tmp/portage-ondisk/portage/app-office/libreoffice-5.3.3.2/temp/ccKfBKCF.ltrans20.ltrans.o: In function `MultiLineEdit::~MultiLineEdit()':
<artificial>:(.text+0x3b3): undefined reference to `vtable for MultiLineEdit'
<artificial>:(.text+0x3e0): undefined reference to `VTT for MultiLineEdit'
/var/tmp/portage-ondisk/portage/app-office/libreoffice-5.3.3.2/temp/ccKfBKCF.ltrans20.ltrans.o: In function `makeLicenseView':
<artificial>:(.text+0x7be): undefined reference to `vtable for MultiLineEdit'
collect2: error: ld returned 1 exit status
make[1]: *** [/var/tmp/portage-ondisk/portage/app-office/libreoffice-5.3.3.2/work/libreoffice-5.3.3.2/desktop/Library_deploymentgui.mk:10: /var/tmp/portage-ondisk/portage/app-office/libreoffice-5.3.3.2/work/libreoffice-5.3.3.2/instdir/program/libdeploymentgui.so] Error 1
make[1]: *** Waiting for unfinished jobs....


Expected Results:
Should compile like before


Reproducible: Always

User Profile Reset: No

Additional Info:


User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.61 Safari/537.36