make this build on SunOS/Solaris

README.md

@@ -430,6 +430,17 @@ doas make install
 
 Build monero: `env DEVELOPER_LOCAL_TOOLS=1 BOOST_ROOT=/usr/local make release-static`
 
+### On Solaris:
+
+The default Solaris linker can't be used, you have to install GNU ld, then run cmake manually with the path to your copy of GNU ld:
+
+        mkdir -p build/release
+        cd build/release
+        cmake -DCMAKE_LINKER=/path/to/ld -D CMAKE_BUILD_TYPE=Release ../..
+        cd ../..
+
+Then you can run make as usual.
+
 ### On Linux for Android (using docker):
 
         # Build image (select android64.Dockerfile for aarch64)