diff --git a/_constraints b/_constraints
new file mode 100644
index 0000000..290ed62
--- /dev/null
+++ b/_constraints
@@ -0,0 +1,7 @@
+<constraints>
+  <hardware>
+    <physicalmemory>
+      <size unit="M">2048</size>
+    </physicalmemory>
+  </hardware>
+</constraints> 
diff --git a/telegram-desktop.changes b/telegram-desktop.changes
index 3de3a0d..5f5e079 100644
--- a/telegram-desktop.changes
+++ b/telegram-desktop.changes
@@ -1,3 +1,11 @@
+-------------------------------------------------------------------
+Wed Jun 21 08:40:07 UTC 2017 - badshah400@gmail.com
+
+- For openSUSE Leap, use gcc6 from the Update repository (gcc6
+  from OSS is uninstallable).
+- Add a _constraints file to restrict building to hardware with at
+  2 GB of physical memory.
+
 -------------------------------------------------------------------
 Sun Jun  4 22:04:45 UTC 2017 - badshah400@gmail.com
 
diff --git a/telegram-desktop.spec b/telegram-desktop.spec
index 2c4bcad..8d44d5b 100644
--- a/telegram-desktop.spec
+++ b/telegram-desktop.spec
@@ -37,7 +37,12 @@ BuildRequires:  desktop-file-utils
 BuildRequires:  ffmpeg-devel
 BuildRequires:  fontconfig-devel
 BuildRequires:  freetype-devel
+%if 0%{?suse_version} <= 1320
+BuildRequires:  gcc6-c++ >= 6.2
+BuildRequires:  libgcc_s1 >= 6.2
+%else
 BuildRequires:  gcc-c++ >= 5.0
+%endif
 BuildRequires:  libXfixes-devel
 BuildRequires:  libexpat-devel
 BuildRequires:  libjpeg-devel
@@ -144,6 +149,10 @@ cd %{_builddir}/Libraries
 ln -s %{_builddir}/breakpad ./breakpad
 cd breakpad
 ln -s %{_builddir}/breakpad-lss ./src/third_party/lss
+%if 0%{?suse_version} <= 1320
+export CXX='g++-6'
+export GCC='gcc-6'
+%endif
 # FIXME: you should use the %%configure macro
 ./configure
 make %{?_smp_mflags}
@@ -157,6 +166,7 @@ patch -p1 < patch-%{version}.diff
 cd %{_builddir}/tdesktop/Telegram/gyp
 # patch qt.gypi to change libxkbcommon path
 ../../../Libraries/gyp/gyp \
+    -DCMAKE_CXX_COMPILER='g++-6' \
     -Dlinux_path_qt="%{_builddir}/Libraries/QtStatic" \
     -Dqt_version="5.6.0" \
     -Dlinux_lib_ssl=-lssl \
@@ -167,7 +177,13 @@ cd %{_builddir}/tdesktop/Telegram/gyp
 # build Telegram
 cd %{_builddir}/tdesktop/out/Release
 # FIXME: you should use %%cmake macros
+%if 0%{?suse_version} <= 1320
+export CXX='g++-6'
+export GCC='gcc-6'
+CC=gcc-6 CXX=g++-6 cmake .
+%else
 cmake .
+%endif
 make %{?_smp_mflags}
 chrpath --delete Telegram