Add note to readme

Author: antoyo

Readme.md

@@ -205,6 +205,19 @@ error: failed to build archive: failed to open object file: No such file or dire
 That can be caused by the fact that you try to compile with `lto = "fat"`, but you didn't compile the sysroot with LTO.
 (Not sure if that's the reason since I cannot reproduce anymore. Maybe it happened when forgetting setting `FAT_LTO`.)
 
+### ld: cannot find crtbegin.o
+
+When compiling an executable with libgccijt, if setting the `*LIBRARY_PATH` variables to the install directory, you will get the following errors:
+
+```
+ld: cannot find crtbegin.o: No such file or directory
+ld: cannot find -lgcc: No such file or directory
+ld: cannot find -lgcc: No such file or directory
+libgccjit.so: error: error invoking gcc driver
+```
+
+To fix this, set the variables to `gcc-build/build/gcc`.
+
 ### How to debug GCC LTO
 
 Run do the command with `-v -save-temps` and then extract the `lto1` line from the output and run that under the debugger.