diff --git a/var/spack/repos/builtin/packages/gcc/detection_test.yaml b/var/spack/repos/builtin/packages/gcc/detection_test.yaml
index 7269c0301c1..4ac823c1bf5 100644
--- a/var/spack/repos/builtin/packages/gcc/detection_test.yaml
+++ b/var/spack/repos/builtin/packages/gcc/detection_test.yaml
@@ -26,7 +26,7 @@ paths:
     extra_attributes:
       compilers:
         c: ".*/bin/gcc"
-        cxx: ".*/bin/g++"
+        cxx: ".*/bin/g\\+\\+"
 
 # Mock a version < 7 of GCC that requires -dumpversion and
 # errors with -dumpfullversion
diff --git a/var/spack/repos/builtin/packages/nvhpc/detection_test.yaml b/var/spack/repos/builtin/packages/nvhpc/detection_test.yaml
index bdf1c6b596c..fc8ccfafc84 100644
--- a/var/spack/repos/builtin/packages/nvhpc/detection_test.yaml
+++ b/var/spack/repos/builtin/packages/nvhpc/detection_test.yaml
@@ -24,7 +24,7 @@ paths:
     extra_attributes:
       compilers:
         c: ".*/bin/nvc"
-        cxx: ".*/bin/nvc++"
+        cxx: ".*/bin/nvc\\+\\+"
         fortran: ".*/bin/nvfortran"
 - layout:
   - executables:
@@ -51,7 +51,7 @@ paths:
     extra_attributes:
       compilers:
         c: ".*/bin/nvc"
-        cxx: ".*/bin/nvc++"
+        cxx: ".*/bin/nvc\\+\\+"
         fortran: ".*/bin/nvfortran"
 - layout:
   - executables:
@@ -78,5 +78,5 @@ paths:
     extra_attributes:
       compilers:
         c: ".*/bin/nvc"
-        cxx: ".*/bin/nvc++"
+        cxx: ".*/bin/nvc\\+\\+"
         fortran: ".*/bin/nvfortran"