Embedded systems have become prominent targets for cyberattacks. To exploit firmware's memory corruption vulnerabilities, cybercriminals harvest reusable code gadgets from the large shared library codebase (e.g., uClibc). Unfortunately, unlike their desktop counterparts, embedded systems lack essential computing resources to enforce security hardening techniques. Recently, we have witnessed a surge of software debloating as a new defense mechanism against code-reuse attacks; it erases unused code to significantly diminish the possibilities of constructing reusable gadgets. Because of the single firmware image update style, static library debloating shows promise to fortify embedded systems without compromising performance and forward compatibility. However, static library debloating on stripped binaries (e.g., firmware's shared libraries) is still an enormous challenge.In this paper, we show that this challenge is not insurmountable for MIPS firmware. We develop a novel system, named đTrimmer, to identify and wipe out unused basic blocks from shared libraries' binary code, without causing additional runtime overhead or memory consumption. We propose a new method to identify addresstaken blocks/functions, which further help us maintain an interprocedural control flow graph to conservatively include library code that could be potentially used by firmware. By capturing address access patterns for position-independent code, we circumvent the challenge of determining code-pointer targets and safely eliminate unused code. We run đTrimmer to debloat shared libraries for SPEC CPU2017 benchmarks, popular firmware applications (e.g., Apache, BusyBox, and OpenSSL), and a real-world wireless router firmware image. Our experiments show that not only does đTrimmer deliver functional programs, but also it can cut the exposed code surface and eliminate various reusable code gadgets remarkably. đTrimmer's debloating capability can compete with the static linking results.