diff --git a/devel/llvm10/Makefile b/devel/llvm10/Makefile
index 2832253564c5..a79b93e45983 100644
--- a/devel/llvm10/Makefile
+++ b/devel/llvm10/Makefile
@@ -60,11 +60,6 @@ CMAKE_ARGS+=	-DPYTHON_EXECUTABLE=${PYTHON_CMD} \
 # LLVM likes to pick up ${LOCALBASE}/lib/libtinfo.so.*
 CMAKE_ARGS+=	-DLLVM_ENABLE_TERMINFO=OFF
 
-# Disable assertions.  They should be disabled by cmake, but USES=cmake
-# overrides -DCMAKE_*_FLAGS_RELEASE.
-CFLAGS+=	-DNDEBUG
-CXXFLAGS+=	-DNDEBUG
-
 OPTIONS_DEFINE=	BE_AMDGPU CLANG DOCS EXTRAS LIT LLD LLDB PYCLANG
 OPTIONS_DEFINE_aarch64=	OPENMP
 OPTIONS_DEFINE_amd64=	COMPILER_RT GOLD OPENMP
diff --git a/devel/llvm11/Makefile b/devel/llvm11/Makefile
index 90debe37315c..5a2587e4d02f 100644
--- a/devel/llvm11/Makefile
+++ b/devel/llvm11/Makefile
@@ -54,11 +54,6 @@ CMAKE_ARGS+=	-DLLVM_ENABLE_Z3_SOLVER=OFF
 # LLVM likes to pick up ${LOCALBASE}/lib/libtinfo.so.*
 CMAKE_ARGS+=	-DLLVM_ENABLE_TERMINFO=OFF
 
-# Disable assertions.  They should be disabled by cmake, but USES=cmake
-# overrides -DCMAKE_*_FLAGS_RELEASE.
-CFLAGS+=	-DNDEBUG
-CXXFLAGS+=	-DNDEBUG
-
 OPTIONS_DEFINE=	BE_AMDGPU BE_WASM CLANG DOCS EXTRAS LIT LLD LLDB PYCLANG
 OPTIONS_DEFINE_aarch64=	OPENMP
 OPTIONS_DEFINE_amd64=	COMPILER_RT GOLD OPENMP
diff --git a/devel/llvm12/Makefile b/devel/llvm12/Makefile
index 1930a23dc473..73d1f2e86b2d 100644
--- a/devel/llvm12/Makefile
+++ b/devel/llvm12/Makefile
@@ -64,11 +64,6 @@ CMAKE_ARGS+=	-DLLVM_ENABLE_LIBEDIT=OFF
 # LLVM likes to pick up ${LOCALBASE}/lib/libtinfo.so.*
 CMAKE_ARGS+=	-DLLVM_ENABLE_TERMINFO=OFF
 
-# Disable assertions.  They should be disabled by cmake, but USES=cmake
-# overrides -DCMAKE_*_FLAGS_RELEASE.
-CFLAGS+=	-DNDEBUG
-CXXFLAGS+=	-DNDEBUG
-
 OPTIONS_DEFINE=	BE_AMDGPU BE_WASM CLANG DOCS EXTRAS LIT LLD PYCLANG
 OPTIONS_DEFINE_aarch64=	OPENMP
 OPTIONS_DEFINE_amd64=	COMPILER_RT GOLD LLDB OPENMP
diff --git a/devel/llvm13/Makefile b/devel/llvm13/Makefile
index 955b78d82c73..414a74af375d 100644
--- a/devel/llvm13/Makefile
+++ b/devel/llvm13/Makefile
@@ -73,11 +73,6 @@ CMAKE_ARGS+=	-DLLVM_ENABLE_LIBEDIT=OFF
 # LLVM likes to pick up ${LOCALBASE}/lib/libtinfo.so.*
 CMAKE_ARGS+=	-DLLVM_ENABLE_TERMINFO=OFF
 
-# Disable assertions.  They should be disabled by cmake, but USES=cmake
-# overrides -DCMAKE_*_FLAGS_RELEASE.
-CFLAGS+=	-DNDEBUG
-CXXFLAGS+=	-DNDEBUG
-
 OPTIONS_DEFINE=	BE_AMDGPU BE_WASM CLANG DOCS EXTRAS FLANG LIT LLD LLDB MLIR PYCLANG
 OPTIONS_DEFINE_aarch64=	OPENMP
 OPTIONS_DEFINE_amd64=	COMPILER_RT GOLD OPENMP
diff --git a/devel/llvm14/Makefile b/devel/llvm14/Makefile
index ec7749aa3d93..25c95a6fb6b2 100644
--- a/devel/llvm14/Makefile
+++ b/devel/llvm14/Makefile
@@ -77,11 +77,6 @@ CMAKE_ARGS+=	-DLLVM_ENABLE_LIBEDIT=OFF
 # LLVM likes to pick up ${LOCALBASE}/lib/libtinfo.so.*
 CMAKE_ARGS+=	-DLLVM_ENABLE_TERMINFO=OFF
 
-# Disable assertions.  They should be disabled by cmake, but USES=cmake
-# overrides -DCMAKE_*_FLAGS_RELEASE.
-CFLAGS+=	-DNDEBUG
-CXXFLAGS+=	-DNDEBUG
-
 OPTIONS_DEFINE=	BE_AMDGPU BE_WASM CLANG DOCS EXTRAS FLANG LIT LLD LLDB MLIR PYCLANG
 OPTIONS_DEFINE_aarch64=	OPENMP
 OPTIONS_DEFINE_amd64=	COMPILER_RT GOLD OPENMP
diff --git a/devel/llvm15/Makefile b/devel/llvm15/Makefile
index 91ef79f08208..900606601e2a 100644
--- a/devel/llvm15/Makefile
+++ b/devel/llvm15/Makefile
@@ -84,11 +84,6 @@ CMAKE_ARGS+=	-DLLVM_ENABLE_LIBEDIT=OFF
 # LLVM likes to pick up ${LOCALBASE}/lib/libtinfo.so.*
 CMAKE_ARGS+=	-DLLVM_ENABLE_TERMINFO=OFF
 
-# Disable assertions.  They should be disabled by cmake, but USES=cmake
-# overrides -DCMAKE_*_FLAGS_RELEASE.
-CFLAGS+=	-DNDEBUG
-CXXFLAGS+=	-DNDEBUG
-
 OPTIONS_DEFINE=	BE_AMDGPU BE_WASM CLANG DOCS LLD STATIC_LIBS
 OPTIONS_DEFAULT=	BE_AMDGPU BE_WASM CLANG LLD
 OPTIONS_SINGLE=		BACKENDS
diff --git a/devel/llvm16/Makefile b/devel/llvm16/Makefile
index c9ee00d8f6fa..d8b29aa36f97 100644
--- a/devel/llvm16/Makefile
+++ b/devel/llvm16/Makefile
@@ -85,11 +85,6 @@ CMAKE_ARGS+=	-DLLVM_ENABLE_LIBEDIT=OFF
 # LLVM likes to pick up ${LOCALBASE}/lib/libtinfo.so.*
 CMAKE_ARGS+=	-DLLVM_ENABLE_TERMINFO=OFF
 
-# Disable assertions.  They should be disabled by cmake, but USES=cmake
-# overrides -DCMAKE_*_FLAGS_RELEASE.
-CFLAGS+=	-DNDEBUG
-CXXFLAGS+=	-DNDEBUG
-
 OPTIONS_DEFINE=	BE_AMDGPU BE_WASM CLANG COMPILER_RT DOCS LLD STATIC_LIBS
 OPTIONS_DEFAULT=	BE_AMDGPU BE_WASM CLANG LLD
 OPTIONS_SINGLE=		BACKENDS
diff --git a/devel/llvm17/Makefile b/devel/llvm17/Makefile
index fd4faad41a89..2a0873547258 100644
--- a/devel/llvm17/Makefile
+++ b/devel/llvm17/Makefile
@@ -88,11 +88,6 @@ CMAKE_ARGS+=	-DLLVM_ENABLE_LIBEDIT=OFF
 # LLVM likes to pick up ${LOCALBASE}/lib/libtinfo.so.*
 CMAKE_ARGS+=	-DLLVM_ENABLE_TERMINFO=OFF
 
-# Disable assertions.  They should be disabled by cmake, but USES=cmake
-# overrides -DCMAKE_*_FLAGS_RELEASE.
-CFLAGS+=	-DNDEBUG
-CXXFLAGS+=	-DNDEBUG
-
 OPTIONS_DEFINE=	BE_AMDGPU BE_WASM CLANG COMPILER_RT DOCS LLD STATIC_LIBS
 OPTIONS_DEFAULT=	BE_AMDGPU BE_WASM CLANG LLD
 OPTIONS_SINGLE=		BACKENDS
diff --git a/devel/llvm18/Makefile b/devel/llvm18/Makefile
index cd0eea7defa2..9116e16cc02a 100644
--- a/devel/llvm18/Makefile
+++ b/devel/llvm18/Makefile
@@ -86,11 +86,6 @@ CMAKE_ARGS+=	-DLLVM_ENABLE_LIBEDIT=OFF
 CMAKE_ARGS+=	-DLLVM_ENABLE_TERMINFO=OFF
 CMAKE_ARGS+=	-DLLVM_VERSION_SUFFIX=
 
-# Disable assertions.  They should be disabled by cmake, but USES=cmake
-# overrides -DCMAKE_*_FLAGS_RELEASE.
-CFLAGS+=	-DNDEBUG
-CXXFLAGS+=	-DNDEBUG
-
 OPTIONS_DEFINE=	BE_AMDGPU BE_WASM CLANG COMPILER_RT DOCS LLD STATIC_LIBS
 OPTIONS_DEFAULT=	BE_AMDGPU BE_WASM CLANG LLD
 OPTIONS_SINGLE=		BACKENDS