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+1) C++ ABI
+The C++ ABI generated by GCC version 2.95, 2.96, 3.0, and 3.1.1 are
+incompatible with each other. This means that, for examples, apps compiled
+with GCC 2.95 cannot link to libraries compiled with GCC 3.2.
+
+GCC 3.4 is the latest ABI at the moment (April 2005). But the most widely
+used ABI at the moment is the GCC 3.2 ABI.
+
+2) Symbol collisions, be aware of what libraries are implicitly linked in.
+Imagine the following situation:
+- foo contains the symbol foobar (a function).
+- libbar contains a symbol with the same name, but is a totally different
+  function.
+- foo is linked to libbar.
+When foo tries to call foobar(), it's undefined whether it will call the
+foobar() from it's own binary, or the one from libbar. Depending on what
+those functions do, foo may crash or do something it isn't supposed to do.
+
+Solution: rtld features, -Bgroup. However, at this moment these are not
+supported by glibc. Until they are, keep these in mind:
+- You should mark all functions that you do not want to export (or show up
+  in the symbol table) as static.
+- If you're a library, you should namespace all functions.
+- Internal functions that are used within a library, but across multiple
+  .c files, should be prefixed by a _ or __.
+
+3) Linking against shared versions of X11 extension libs
+Some X libraries, such as libXrender, are originally not shared libraries.
+Distributions just created shared library versions to save memory. So
+some distributions don't ship the shared versions at all. Apbuild
+automatically statically links some of those X libraries (you can turn
+this behavior off of course).
+
+4) Usage of sys_errlist
+
+5) Don't use TLS (the __thread keyword).