Add GCC and GNU Make to the Nix flake development environment so that `ruff` can be compiled. (#16090)

* Add gcc and GNU make to the Nix flake

* Newsfile

Signed-off-by: Olivier Wilkinson (reivilibre) <oliverw@matrix.org>

* unset LD_LIBRARY_PATH

---------

Signed-off-by: Olivier Wilkinson (reivilibre) <oliverw@matrix.org>

changelog.d/16090.misc

@@ -0,0 +1 @@
+Add GCC and GNU Make to the Nix flake development environment so that `ruff` can be compiled.

flake.nix

@@ -89,6 +89,10 @@
                   })
                   # The rust-analyzer language server implementation.
                   rust-analyzer
+                  # GCC includes a linker; needed for building `ruff`
+                  gcc
+                  # Needed for building `ruff`
+                  gnumake
 
                   # Native dependencies for running Synapse.
                   icu
@@ -236,6 +240,19 @@
                   URI
                   YAMLLibYAML
                 ]}";
+
+                # Clear the LD_LIBRARY_PATH environment variable on shell init.
+                #
+                # By default, devenv will set LD_LIBRARY_PATH to point to .devenv/profile/lib. This causes
+                # issues when we include `gcc` as a dependency to build C libraries, as the version of glibc
+                # that the development environment's cc compiler uses may differ from that of the system.
+                #
+                # When LD_LIBRARY_PATH is set, system tools will attempt to use the development environment's
+                # libraries. Which, when built against an different glibc version lead, to "version 'GLIBC_X.YY' not
+                # found" errors.
+                enterShell = ''
+                  unset LD_LIBRARY_PATH
+                '';
               }
             ];
           };