cde: add -fcommon workaround

Workaround build failure on -fno-common toolchains like upstream
gcc-10. Otherwise build fails as:

    ld: ../readelf-mini/libreadelf-mini.a(dwarf.o):/build/source/readelf-mini/dwarf.c:64:
      multiple definition of `do_wide'; ../readelf-mini/libreadelf-mini.a(readelf-mini.o):/build/source/readelf-mini/readelf-mini.c:170: first defined here

pkgs/tools/package-management/cde/default.nix

@@ -25,6 +25,12 @@ stdenv.mkDerivation rec {
     patchShebangs .
   '';
 
+  # Workaround build failure on -fno-common toolchains like upstream
+  # gcc-10. Otherwise build fails as:
+  #   ld: ../readelf-mini/libreadelf-mini.a(dwarf.o):/build/source/readelf-mini/dwarf.c:64:
+  #     multiple definition of `do_wide'; ../readelf-mini/libreadelf-mini.a(readelf-mini.o):/build/source/readelf-mini/readelf-mini.c:170: first defined here
+  NIX_CFLAGS_COMPILE = "-fcommon";
+
   installPhase = ''
     install -d $out/bin
     install -t $out/bin cde cde-exec
@@ -36,7 +42,7 @@ stdenv.mkDerivation rec {
     license = licenses.gpl3Plus;
     maintainers = [ maintainers.rlupton20 ];
     platforms = platforms.linux;
-    # error: architecture aarch64 is not supported by strace
+    # error: architecture aarch64 is not supported by bundled strace
     badPlatforms = [ "aarch64-linux" ];
   };
 }