Merge pull request #557 from tweag/cc_std

Make the C++ -std flag configurable
tweag · Jun 25, 2024 · ecd3028 · ecd3028
2 parents 7e1d203 + 55afe3b
commit ecd3028
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Showing 4 changed files with 45 additions and 5 deletions.
diff --git a/README.md b/README.md
@@ -124,7 +124,7 @@ nixpkgs_package(
 <pre>
 nixpkgs_cc_configure(<a href="#nixpkgs_cc_configure-name">name</a>, <a href="#nixpkgs_cc_configure-attribute_path">attribute_path</a>, <a href="#nixpkgs_cc_configure-nix_file">nix_file</a>, <a href="#nixpkgs_cc_configure-nix_file_content">nix_file_content</a>, <a href="#nixpkgs_cc_configure-nix_file_deps">nix_file_deps</a>, <a href="#nixpkgs_cc_configure-repositories">repositories</a>,
                      <a href="#nixpkgs_cc_configure-repository">repository</a>, <a href="#nixpkgs_cc_configure-nixopts">nixopts</a>, <a href="#nixpkgs_cc_configure-quiet">quiet</a>, <a href="#nixpkgs_cc_configure-fail_not_supported">fail_not_supported</a>, <a href="#nixpkgs_cc_configure-exec_constraints">exec_constraints</a>,
-                     <a href="#nixpkgs_cc_configure-target_constraints">target_constraints</a>, <a href="#nixpkgs_cc_configure-register">register</a>, <a href="#nixpkgs_cc_configure-cc_lang">cc_lang</a>, <a href="#nixpkgs_cc_configure-cross_cpu">cross_cpu</a>)
+                     <a href="#nixpkgs_cc_configure-target_constraints">target_constraints</a>, <a href="#nixpkgs_cc_configure-register">register</a>, <a href="#nixpkgs_cc_configure-cc_lang">cc_lang</a>, <a href="#nixpkgs_cc_configure-cc_std">cc_std</a>, <a href="#nixpkgs_cc_configure-cross_cpu">cross_cpu</a>)
 </pre>
 
 Use a CC toolchain from Nixpkgs. No-op if not a nix-based platform.
@@ -380,6 +380,20 @@ default is <code>"c++"</code>
 
 string, `"c++"` by default. Used to populate `CXX_FLAG` so the compiler is called in C++ mode. Can be set to `"none"` together with appropriate `copts` in the `cc_library` call: see above.
 
+</p>
+</td>
+</tr>
+<tr id="nixpkgs_cc_configure-cc_std">
+<td><code>cc_std</code></td>
+<td>
+
+optional.
+default is <code>"c++0x"</code>
+
+<p>
+
+string, `"c++0x"` by default. Used to populate `CXX_FLAG` so the compiler uses the given language standard. Can be set to `"none"` together with appropriate `copts` in the `cc_library` call: see above.
+
 </p>
 </td>
 </tr>

diff --git a/toolchains/cc/README.md b/toolchains/cc/README.md
@@ -31,7 +31,7 @@ using `nixpkgs_cc_configure(..., cc_lang = "cuda")` or similar.
 <pre>
 nixpkgs_cc_configure(<a href="#nixpkgs_cc_configure-name">name</a>, <a href="#nixpkgs_cc_configure-attribute_path">attribute_path</a>, <a href="#nixpkgs_cc_configure-nix_file">nix_file</a>, <a href="#nixpkgs_cc_configure-nix_file_content">nix_file_content</a>, <a href="#nixpkgs_cc_configure-nix_file_deps">nix_file_deps</a>, <a href="#nixpkgs_cc_configure-repositories">repositories</a>,
                      <a href="#nixpkgs_cc_configure-repository">repository</a>, <a href="#nixpkgs_cc_configure-nixopts">nixopts</a>, <a href="#nixpkgs_cc_configure-quiet">quiet</a>, <a href="#nixpkgs_cc_configure-fail_not_supported">fail_not_supported</a>, <a href="#nixpkgs_cc_configure-exec_constraints">exec_constraints</a>,
-                     <a href="#nixpkgs_cc_configure-target_constraints">target_constraints</a>, <a href="#nixpkgs_cc_configure-register">register</a>, <a href="#nixpkgs_cc_configure-cc_lang">cc_lang</a>, <a href="#nixpkgs_cc_configure-cross_cpu">cross_cpu</a>)
+                     <a href="#nixpkgs_cc_configure-target_constraints">target_constraints</a>, <a href="#nixpkgs_cc_configure-register">register</a>, <a href="#nixpkgs_cc_configure-cc_lang">cc_lang</a>, <a href="#nixpkgs_cc_configure-cc_std">cc_std</a>, <a href="#nixpkgs_cc_configure-cross_cpu">cross_cpu</a>)
 </pre>
 
 Use a CC toolchain from Nixpkgs. No-op if not a nix-based platform.
@@ -287,6 +287,20 @@ default is <code>"c++"</code>
 
 string, `"c++"` by default. Used to populate `CXX_FLAG` so the compiler is called in C++ mode. Can be set to `"none"` together with appropriate `copts` in the `cc_library` call: see above.
 
+</p>
+</td>
+</tr>
+<tr id="nixpkgs_cc_configure-cc_std">
+<td><code>cc_std</code></td>
+<td>
+
+optional.
+default is <code>"c++0x"</code>
+
+<p>
+
+string, `"c++0x"` by default. Used to populate `CXX_FLAG` so the compiler uses the given language standard. Can be set to `"none"` together with appropriate `copts` in the `cc_library` call: see above.
+
 </p>
 </td>
 </tr>

diff --git a/toolchains/cc/cc.bzl b/toolchains/cc/cc.bzl
@@ -311,6 +311,7 @@ def nixpkgs_cc_configure(
         target_constraints = None,
         register = True,
         cc_lang = "c++",
+        cc_std = "c++0x",
         cross_cpu = ""):
     """Use a CC toolchain from Nixpkgs. No-op if not a nix-based platform.
 
@@ -382,6 +383,7 @@ def nixpkgs_cc_configure(
       target_constraints: Constraints for the target platform.
       register: bool, enabled by default, Whether to register (with `register_toolchains`) the generated toolchain and install it as the default cc_toolchain.
       cc_lang: string, `"c++"` by default. Used to populate `CXX_FLAG` so the compiler is called in C++ mode. Can be set to `"none"` together with appropriate `copts` in the `cc_library` call: see above.
+      cc_std: string, `"c++0x"` by default. Used to populate `CXX_FLAG` so the compiler uses the given language standard. Can be set to `"none"` together with appropriate `copts` in the `cc_library` call: see above.
       cross_cpu: string, `""` by default. Used if you want to add a cross compilation C/C++ toolchain. Set this to the CPU architecture for the target CPU. For example x86_64, would be k8.
     """
     nixopts = list(nixopts)
@@ -413,6 +415,9 @@ def nixpkgs_cc_configure(
             "--argstr",
             "ccLang",
             cc_lang,
+            "--argstr",
+            "ccStd",
+            cc_std,
         ])
     elif nix_expr:
         nixopts.extend([
@@ -425,6 +430,9 @@ def nixpkgs_cc_configure(
             "--argstr",
             "ccLang",
             cc_lang,
+            "--argstr",
+            "ccStd",
+            cc_std,
         ])
     else:
         nixopts.extend([
@@ -434,6 +442,9 @@ def nixpkgs_cc_configure(
             "--argstr",
             "ccLang",
             cc_lang,
+            "--argstr",
+            "ccStd",
+            cc_std,
         ])
 
     # Invoke `cc.nix` which generates `CC_TOOLCHAIN_INFO`.

diff --git a/toolchains/cc/cc.nix b/toolchains/cc/cc.nix
@@ -4,6 +4,7 @@
 , ccExpr ? null
 , ccPkgs ? import <nixpkgs> { config = { }; overlays = [ ]; }
 , ccLang ? "c++"
+, ccStd ? "c++0x"
 }:
 
 let
@@ -165,10 +166,10 @@ pkgs.runCommand "bazel-${cc.orignalName or cc.name}-toolchain"
       include_dirs_for c++
       if is_compiler_option_supported -fno-canonical-system-headers; then
         include_dirs_for c -fno-canonical-system-headers
-        include_dirs_for c++ -std=c++0x -fno-canonical-system-headers
+        include_dirs_for c++ -std=${ccStd} -fno-canonical-system-headers
       elif is_compiler_option_supported -no-canonical-prefixes; then
         include_dirs_for c -no-canonical-prefixes
-        include_dirs_for c++ -std=c++0x -no-canonical-prefixes
+        include_dirs_for c++ -std=${ccStd} -no-canonical-prefixes
       fi
     } 2>&1 | sort -u))
     unset IFS
@@ -201,7 +202,7 @@ pkgs.runCommand "bazel-${cc.orignalName or cc.name}-toolchain"
     )
     CXX_FLAGS=(
       -x ${ccLang}
-      -std=c++0x
+      -std=${ccStd}
     )
     LINK_FLAGS=(
       $(