cc-wrapper: Workaround gnuabielfv{1,2} support deficiency on Clang

pkgs/build-support/cc-wrapper/add-clang-cc-cflags-before.sh

@@ -30,4 +30,8 @@ if $targetPassed && [[ "$targetValue" != "@defaultTarget@" ]] && (( "${NIX_CC_WR
     echo "Warning: supplying the --target $targetValue != @defaultTarget@ argument to a nix-wrapped compiler may not work correctly - cc-wrapper is currently not designed with multi-target compilers in mind. You may want to use an un-wrapped compiler instead." >&2
 elif [[ $0 != *cpp ]]; then
     extraBefore+=(-target @defaultTarget@ @machineFlags@)
+
+    if [[ "@explicitAbiValue@" != "" ]]; then
+        extraBefore+=(-mabi=@explicitAbiValue@)
+    fi
 fi

pkgs/build-support/cc-wrapper/default.nix

@@ -94,12 +94,14 @@ let
     getLib
     getName
     getVersion
+    hasPrefix
     mapAttrsToList
     optional
     optionalAttrs
     optionals
     optionalString
     removePrefix
+    removeSuffix
     replaceStrings
     toList
     versionAtLeast
@@ -900,12 +902,24 @@ stdenvNoCC.mkDerivation {
     ## General Clang support
     ## Needs to go after ^ because the for loop eats \n and makes this file an invalid script
     ##
-    + optionalString isClang ''
-      # Escape twice: once for this script, once for the one it gets substituted into.
-      export machineFlags=${escapeShellArg (escapeShellArgs machineFlags)}
-      export defaultTarget=${targetPlatform.config}
-      substituteAll ${./add-clang-cc-cflags-before.sh} $out/nix-support/add-local-cc-cflags-before.sh
-    ''
+    + optionalString isClang (
+      let
+        hasUnsupportedGnuSuffix = hasPrefix "gnuabielfv" targetPlatform.parsed.abi.name;
+        clangCompatibleConfig =
+          if hasUnsupportedGnuSuffix then
+            removeSuffix (removePrefix "gnu" targetPlatform.parsed.abi.name) targetPlatform.config
+          else
+            targetPlatform.config;
+        explicitAbiValue = if hasUnsupportedGnuSuffix then targetPlatform.parsed.abi.abi else "";
+      in
+      ''
+        # Escape twice: once for this script, once for the one it gets substituted into.
+        export machineFlags=${escapeShellArg (escapeShellArgs machineFlags)}
+        export defaultTarget=${clangCompatibleConfig}
+        export explicitAbiValue=${explicitAbiValue}
+        substituteAll ${./add-clang-cc-cflags-before.sh} $out/nix-support/add-local-cc-cflags-before.sh
+      ''
+    )
 
     ##
     ## Extra custom steps