Preprocessor directives such as texttt{#ifdef} have historically been the predominant mechanism for managing variability in legacy C/C++ codebases. While they offer a simple way to include or exclude code at compilation time, they lack explicit variability representation and make it difficult to reason about features beyond conditional inclusion. Over time, these directives tend to become scattered, redundant, and obsolete—resulting in tangled and rigid implementations that hinder maintenance, reuse, and long-term evolution. With the growing maturity of Software Product Line Engineering (SPLE) and the emergence of industrial tools such as Mobioos Forge, it is now possible to rethink the variability management in legacy systems. Forge enables the specification of variability through feature models, the generation of feature-to-code mappings, and the static derivation of variants without relying on the compiler. These capabilities pave the way for modernizing configurable codebases by making variability explicit, analyzable, and maintainable. In this paper, we present an integrated toolchain for the automated recovery of Software Product Lines from legacy C/C++ systems. Our approach identifies features and their interactions, synthesizes a hierarchical feature model, and generates traceability links to locate feature-specific code fragments. Built as an extension to Mobioos Forge, our tool also leverages its static derivation engine to safely remove obsolete features and generate concrete product variants. We validate our approach on large-scale, real-world open-source systems, including Chromium, which contains over 2500 distinct features. The results demonstrate the effectiveness of our method in revealing hidden variability structures, enabling safe variant generation, and supporting the modernization of legacy configurable systems through SPLE principles.