1 files changed, 15 insertions, 6 deletions
diff --git a/pkgs/build-support/cc-wrapper/add-flags.sh b/pkgs/build-support/cc-wrapper/add-flags.sh
index 5634c82aa285..1edfe8bfc753 100644
--- a/pkgs/build-support/cc-wrapper/add-flags.sh
+++ b/pkgs/build-support/cc-wrapper/add-flags.sh
@@ -1,28 +1,37 @@
 # `-B@out@/bin' forces cc to use ld-wrapper.sh when calling ld.
 export NIX_CFLAGS_COMPILE="-B@out@/bin/ $NIX_CFLAGS_COMPILE"
 
+# Export and assign separately in order that a failing $(..) will fail
+# the script.
+
 if [ -e @out@/nix-support/libc-cflags ]; then
-    export NIX_CFLAGS_COMPILE="$(cat @out@/nix-support/libc-cflags) $NIX_CFLAGS_COMPILE"
+    export NIX_CFLAGS_COMPILE
+    NIX_CFLAGS_COMPILE="$(< @out@/nix-support/libc-cflags) $NIX_CFLAGS_COMPILE"
 fi
 
 if [ -e @out@/nix-support/cc-cflags ]; then
-    export NIX_CFLAGS_COMPILE="$(cat @out@/nix-support/cc-cflags) $NIX_CFLAGS_COMPILE"
+    export NIX_CFLAGS_COMPILE
+    NIX_CFLAGS_COMPILE="$(< @out@/nix-support/cc-cflags) $NIX_CFLAGS_COMPILE"
 fi
 
 if [ -e @out@/nix-support/gnat-cflags ]; then
-    export NIX_GNATFLAGS_COMPILE="$(cat @out@/nix-support/gnat-cflags) $NIX_GNATFLAGS_COMPILE"
+    export NIX_GNATFLAGS_COMPILE
+    NIX_GNATFLAGS_COMPILE="$(< @out@/nix-support/gnat-cflags) $NIX_GNATFLAGS_COMPILE"
 fi
 
 if [ -e @out@/nix-support/libc-ldflags ]; then
-    export NIX_LDFLAGS+=" $(cat @out@/nix-support/libc-ldflags)"
+    export NIX_LDFLAGS
+    NIX_LDFLAGS+=" $(< @out@/nix-support/libc-ldflags)"
 fi
 
 if [ -e @out@/nix-support/cc-ldflags ]; then
-    export NIX_LDFLAGS+=" $(cat @out@/nix-support/cc-ldflags)"
+    export NIX_LDFLAGS
+    NIX_LDFLAGS+=" $(< @out@/nix-support/cc-ldflags)"
 fi
 
 if [ -e @out@/nix-support/libc-ldflags-before ]; then
-    export NIX_LDFLAGS_BEFORE="$(cat @out@/nix-support/libc-ldflags-before) $NIX_LDFLAGS_BEFORE"
+    export NIX_LDFLAGS_BEFORE
+    NIX_LDFLAGS_BEFORE="$(< @out@/nix-support/libc-ldflags-before) $NIX_LDFLAGS_BEFORE"
 fi
 
 export NIX_CC_WRAPPER_FLAGS_SET=1