diff --git a/build/build-clang/build-clang.py b/build/build-clang/build-clang.py
index b52dc7734a93..1013336c346f 100755
--- a/build/build-clang/build-clang.py
+++ b/build/build-clang/build-clang.py
@@ -517,6 +517,18 @@ if __name__ == "__main__":
         extra_asmflags = []
         extra_ldflags = []
 
+        # We want to ensure that the GCC we use for stage 1 always picks up the
+        # binutils it is packaged with, rather than the system binutils, which
+        # might be a much different version and therefore lacking in support for
+        # features GCC expects.
+        binutils_flags = ['-B', os.path.dirname(cc)]
+        if cc.endswith('gcc'):
+            extra_cflags += binutils_flags
+        if cxx.endswith('g++'):
+            extra_cxxflags += binutils_flags
+        if asm.endswith('gcc'):
+            extra_asmflags += binutils_flags
+
         if 'LD_LIBRARY_PATH' in os.environ:
             os.environ['LD_LIBRARY_PATH'] = ('%s/lib64/:%s' %
                                              (gcc_dir, os.environ['LD_LIBRARY_PATH']))
diff --git a/taskcluster/scripts/misc/build-llvm-dsymutil.sh b/taskcluster/scripts/misc/build-llvm-dsymutil.sh
index 406c8a5b7f2e..8fe51a68bb48 100755
--- a/taskcluster/scripts/misc/build-llvm-dsymutil.sh
+++ b/taskcluster/scripts/misc/build-llvm-dsymutil.sh
@@ -56,6 +56,9 @@ cmake \
   -DCMAKE_BUILD_TYPE=Release \
   -DLLVM_TARGETS_TO_BUILD=X86 \
   -DCMAKE_C_COMPILER=$HOME_DIR/src/gcc/bin/gcc \
+  -DCMAKE_CXX_COMPILER=$HOME_DIR/src/gcc/bin/g++ \
+  -DCMAKE_C_FLAGS="-B $HOME_DIR/src/gcc/bin" \
+  -DCMAKE_CXX_FLAGS="-B $HOME_DIR/src/gcc/bin" \
   ..
 
 export LD_LIBRARY_PATH=$HOME_DIR/src/gcc/lib64