ocaml-ng.ocamlPackages_4_00_1.ocaml, ocaml-ng.ocamlPackages_4_08.ocaml: add -fcommon workaround

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

    $ nix build --impure --expr 'with import ./. {}; ocaml-ng.ocamlPackages_4_00_1.ocaml.overrideAttrs (oa: {   NIX_CFLAGS_COMPILE = (["-fno-common"] ++ [oa.NIX_CFLAGS_COMPILE or ""]); })'
    ...
    > ld: libcamlrun.a(startup.o):(.bss+0x800): multiple definition of `caml_code_fragments_table'; libcamlrun.a(backtrace.o):(.bss+0x20): first defined here
    > collect2: error: ld returned 1 exit status

pkgs/development/compilers/ocaml/4.00.1.nix

@@ -21,6 +21,12 @@ stdenv.mkDerivation rec {
     sha256 = "sha256:07g9q9sjk4xsbqix7jxggfp36v15pmqw4bms80g5car0hfbszirn";
   })];
 
+  # Workaround build failure on -fno-common toolchains like upstream
+  # gcc-10. Otherwise build fails as:
+  #   ld: libcamlrun.a(startup.o):(.bss+0x800): multiple definition of
+  #     `caml_code_fragments_table'; libcamlrun.a(backtrace.o):(.bss+0x20): first defined here
+  NIX_CFLAGS_COMPILE = "-fcommon";
+
   prefixKey = "-prefix ";
   configureFlags = [ "-no-tk" ] ++ optionals useX11 [ "-x11lib" xlibsWrapper ];
   buildFlags = [ "world" ] ++ optionals useNativeCompilers [ "bootstrap" "world.opt" ];

pkgs/development/compilers/ocaml/4.01.0.nix

@@ -10,4 +10,10 @@ import ./generic.nix {
       sha256 = "sha256:08mpy7lsiwv8m5qrqc4xzyiv2hri5713gz2qs1nfz02hz1bd79mc"; }
   ];
   sha256 = "03d7ida94s1gpr3gadf4jyhmh5rrszd5s4m4z59daaib25rvfyv7";
+
+  # Workaround build failure on -fno-common toolchains like upstream
+  # gcc-10. Otherwise build fails as:
+  #   ld: libcamlrun.a(startup.o):(.bss+0x800): multiple definition of
+  #     `caml_code_fragments_table'; libcamlrun.a(backtrace.o):(.bss+0x20): first defined here
+  NIX_CFLAGS_COMPILE = "-fcommon";
 }

pkgs/development/compilers/ocaml/4.02.nix

@@ -10,4 +10,10 @@ import ./generic.nix {
       sha256 = "sha256:12sw512kpwk0xf2g6j0h5vqgd8xcmgrvgyilx6fxbd6bnfv1yib9"; }
   ];
   sha256 = "1qwwvy8nzd87hk8rd9sm667nppakiapnx4ypdwcrlnav2dz6kil3";
+
+  # Workaround build failure on -fno-common toolchains like upstream
+  # gcc-10. Otherwise build fails as:
+  #   ld: libcamlrun.a(startup.o):(.bss+0x800): multiple definition of
+  #     `caml_code_fragments_table'; libcamlrun.a(backtrace.o):(.bss+0x20): first defined here
+  NIX_CFLAGS_COMPILE = "-fcommon";
 }

pkgs/development/compilers/ocaml/4.03.nix

@@ -9,4 +9,10 @@ import ./generic.nix {
     { url = "https://github.com/ocaml/ocaml/commit/a8b2cc3b40f5269ce8525164ec2a63b35722b22b.patch";
       sha256 = "sha256:1rrknmrk86xrj2k3hznnjk1gwnliyqh125zabg1hvy6dlvml9b0x"; }
   ];
+
+  # Workaround build failure on -fno-common toolchains like upstream
+  # gcc-10. Otherwise build fails as:
+  #   ld: libcamlrun.a(startup.o):(.bss+0x800): multiple definition of
+  #     `caml_code_fragments_table'; libcamlrun.a(backtrace.o):(.bss+0x20): first defined here
+  NIX_CFLAGS_COMPILE = "-fcommon";
 }

pkgs/development/compilers/ocaml/4.04.nix

@@ -12,4 +12,10 @@ import ./generic.nix {
     { url = "https://github.com/ocaml/ocaml/commit/6bcff7e6ce1a43e088469278eb3a9341e6a2ca5b.patch";
       sha256 = "sha256:1hd45f7mwwrrym2y4dbcwklpv0g94avbz7qrn81l7w8mrrj3bngi"; }
   ];
+
+  # Workaround build failure on -fno-common toolchains like upstream
+  # gcc-10. Otherwise build fails as:
+  #   ld: libcamlrun.a(startup.o):(.bss+0x800): multiple definition of
+  #     `caml_code_fragments_table'; libcamlrun.a(backtrace.o):(.bss+0x20): first defined here
+  NIX_CFLAGS_COMPILE = "-fcommon";
 }

pkgs/development/compilers/ocaml/4.05.nix

@@ -12,4 +12,10 @@ import ./generic.nix {
     { url = "https://github.com/ocaml/ocaml/commit/50c2d1275e537906ea144bd557fde31e0bf16e5f.patch";
       sha256 = "sha256:0ck9b2dpgg5k2p9ndbgniql24h35pn1bbpxjvk69j715lswzy4mh"; }
   ];
+
+  # Workaround build failure on -fno-common toolchains like upstream
+  # gcc-10. Otherwise build fails as:
+  #   ld: libcamlrun.a(startup.o):(.bss+0x800): multiple definition of
+  #     `caml_code_fragments_table'; libcamlrun.a(backtrace.o):(.bss+0x20): first defined here
+  NIX_CFLAGS_COMPILE = "-fcommon";
 }

pkgs/development/compilers/ocaml/4.06.nix

@@ -12,4 +12,10 @@ import ./generic.nix {
     { url = "https://github.com/ocaml/ocaml/commit/137a4ad167f25fe1bee792977ed89f30d19bcd74.patch";
       sha256 = "sha256:0izsf6rm3677vbbx0snkmn9pkfcsayrdwz3ipiml5wjiaysnchjz"; }
   ];
+
+  # Workaround build failure on -fno-common toolchains like upstream
+  # gcc-10. Otherwise build fails as:
+  #   ld: libcamlrun.a(startup.o):(.bss+0x800): multiple definition of
+  #     `caml_code_fragments_table'; libcamlrun.a(backtrace.o):(.bss+0x20): first defined here
+  NIX_CFLAGS_COMPILE = "-fcommon";
 }

pkgs/development/compilers/ocaml/4.07.nix

@@ -12,4 +12,10 @@ import ./generic.nix {
     { url = "https://github.com/ocaml/ocaml/commit/00b8c4d503732343d5d01761ad09650fe50ff3a0.patch";
       sha256 = "sha256:02cfya5ff5szx0fsl5x8ax76jyrla9zmf3qxavf3adhwq5ssrfcv"; }
   ];
+
+  # Workaround build failure on -fno-common toolchains like upstream
+  # gcc-10. Otherwise build fails as:
+  #   ld: libcamlrun.a(startup.o):(.bss+0x800): multiple definition of
+  #     `caml_code_fragments_table'; libcamlrun.a(backtrace.o):(.bss+0x20): first defined here
+  NIX_CFLAGS_COMPILE = "-fcommon";
 }

pkgs/development/compilers/ocaml/4.08.nix

@@ -15,4 +15,10 @@ import ./generic.nix {
     { url = "https://github.com/ocaml/ocaml/commit/17df117b4939486d3285031900587afce5262c8c.patch";
       sha256 = "sha256:1b3jc6sj2k23yvfwrv6nc1f4x2n2biqbhbbp74aqb6iyqyjsq35n"; }
   ];
+
+  # Workaround build failure on -fno-common toolchains like upstream
+  # gcc-10. Otherwise build fails as:
+  #   ld: libcamlrun.a(startup.o):(.bss+0x800): multiple definition of
+  #     `caml_code_fragments_table'; libcamlrun.a(backtrace.o):(.bss+0x20): first defined here
+  NIX_CFLAGS_COMPILE = "-fcommon";
 }