Better fix?

Author: hamishmack

compiler/ghc/default.nix

@@ -347,6 +347,10 @@ let
       #        disableLargeAddress space conditional on iOS = true.
       + lib.optionalString (stdenv.targetPlatform.isDarwin && stdenv.targetPlatform.isAarch64)
         " '*.*.ghc.c.opts += -optc-mcpu=apple-a7 -optc-march=armv8-a+norcpc'"
+      + lib.optionalString (targetPlatform.isAndroid && targetPlatform.isAarch32)
+        " '*.*.ghc.c.opts += -optc-march=armv7-a -optc-mfloat-abi=softfp -optc-mfpu=vfpv3-d16'"
+      + lib.optionalString (targetPlatform.isAndroid && targetPlatform.isAarch64)
+        " '*.*.ghc.c.opts += -optc-march=armv8-a'"
       # For GHC versions in the 9.x range that don't support the +native_bignum flavour transformer yet
       + lib.optionalString ((enableNativeBignum && !hadrianHasNativeBignumFlavour))
         " --bignum=native"
@@ -805,11 +809,6 @@ stdenv.mkDerivation (rec {
     if [[ -f rts/win32/ThrIOManager.c ]]; then
       substituteInPlace rts/win32/ThrIOManager.c --replace rts\\OSThreads.h rts/OSThreads.h
     fi
-  ''
-  + lib.optionalString (targetPlatform.isAndroid && targetPlatform.isAarch32) ''
-    export NIX_CFLAGS_COMPILE_${
-        lib.replaceStrings ["-" "."] ["_" "_"] stdenv.targetPlatform.config
-      }+=" -march=armv7-a -mfloat-abi=softfp -mfpu=vfpv3-d16"
   '';
   # Same hack as 'preBuild'
   preInstall = lib.optionalString stdenv.buildPlatform.isDarwin ''