diff --git a/.buckconfig b/.buckconfig
index 483f6053b26..1d0d1153008 100644
--- a/.buckconfig
+++ b/.buckconfig
@@ -1,7 +1,7 @@
 [cxx]
-  cppflags = -DXXH_NAMESPACE=ZSTD_ -DZSTD_LEGACY_SUPPORT=4
+  cppflags = -DXXH_NAMESPACE=ZSTD_ -DZSTD_LEGACY_SUPPORT=0
   cflags = -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement -Wstrict-prototypes -Wundef -Wpointer-arith
-  cxxppflags = -DXXH_NAMESPACE=ZSTD_ -DZSTD_LEGACY_SUPPORT=4
+  cxxppflags = -DXXH_NAMESPACE=ZSTD_ -DZSTD_LEGACY_SUPPORT=0
   cxxflags = -std=c++11 -Wno-deprecated-declarations
   gtest_dep = //contrib/pzstd:gtest
 
diff --git a/.github/workflows/dev-long-tests.yml b/.github/workflows/dev-long-tests.yml
index 55eb0c5d7a9..4b0f6c2acee 100644
--- a/.github/workflows/dev-long-tests.yml
+++ b/.github/workflows/dev-long-tests.yml
@@ -160,6 +160,16 @@ jobs:
     - name: clang + ASan + UBSan + Fuzz Test
       run: CC=clang FUZZER_FLAGS="--long-tests" make clean uasan-fuzztest
 
+  # the only job decoding real legacy frames under sanitizers.
+  # fuzzers do build these decoders, but only reach them if an input
+  # happens to carry a legacy magic number.
+  clang-asan-ubsan-legacy:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # tag=v7.0.1
+    - name: clang + ASan + UBSan + legacy decoders
+      run: CC=clang make uasan-test-legacy
+
   gcc-asan-ubsan-fuzz32:
     runs-on: ubuntu-latest
     steps:
diff --git a/.github/workflows/dev-short-tests.yml b/.github/workflows/dev-short-tests.yml
index acd32363992..45c7a702be7 100644
--- a/.github/workflows/dev-short-tests.yml
+++ b/.github/workflows/dev-short-tests.yml
@@ -237,6 +237,7 @@ jobs:
             -Dbin_tests=true \
             -Dbin_contrib=true \
             -Ddefault_library=both \
+            -Dlegacy_level=1 \
             build/meson mesonBuild
           ninja -C mesonBuild/
           meson test -C mesonBuild/ --print-errorlogs
diff --git a/build/cmake/programs/CMakeLists.txt b/build/cmake/programs/CMakeLists.txt
index 5e239e32a3d..ec23787bb6e 100644
--- a/build/cmake/programs/CMakeLists.txt
+++ b/build/cmake/programs/CMakeLists.txt
@@ -16,11 +16,6 @@ set(LIBRARY_DIR ${ZSTD_SOURCE_DIR}/lib)
 set(PROGRAMS_DIR ${ZSTD_SOURCE_DIR}/programs)
 include_directories(${PROGRAMS_DIR} ${LIBRARY_DIR} ${LIBRARY_DIR}/common ${LIBRARY_DIR}/compress ${LIBRARY_DIR}/dictBuilder)
 
-if (ZSTD_LEGACY_SUPPORT)
-    set(PROGRAMS_LEGACY_DIR ${PROGRAMS_DIR}/legacy)
-    include_directories(${PROGRAMS_LEGACY_DIR} ${LIBRARY_DIR}/legacy)
-endif ()
-
 if (ZSTD_PROGRAMS_LINK_SHARED)
     set(PROGRAMS_ZSTD_LINK_TARGET libzstd_shared)
 else ()
diff --git a/build/meson/tests/meson.build b/build/meson/tests/meson.build
index 71ffc50693d..dcfc07c67a9 100644
--- a/build/meson/tests/meson.build
+++ b/build/meson/tests/meson.build
@@ -102,12 +102,11 @@ invalidDictionaries = executable('invalidDictionaries',
   dependencies: [ libzstd_dep ],
   install: false)
 
-if 0 < legacy_level and legacy_level <= 4
+if legacy_level > 0
   legacy_sources = [join_paths(zstd_rootdir, 'tests/legacy.c')]
+  # the test adapts to ZSTD_LEGACY_SUPPORT, set project wide from legacy_level
   legacy = executable('legacy',
     legacy_sources,
-    # Use -Dlegacy_level build option to control it
-    #c_args: '-DZSTD_LEGACY_SUPPORT=4',
     dependencies: [ libzstd_dep ],
     install: false)
 endif
@@ -199,7 +198,7 @@ test('test-zstream-3',
   timeout: 120)
 test('test-longmatch', longmatch, timeout: 36)
 test('test-invalidDictionaries', invalidDictionaries) # should be fast
-if 0 < legacy_level and legacy_level <= 4
+if legacy_level > 0
   test('test-legacy', legacy) # should be fast
 endif
 test('test-decodecorpus',
diff --git a/contrib/VS2005/zstd/zstd.vcproj b/contrib/VS2005/zstd/zstd.vcproj
index e37ebee3911..979a7f70e4e 100644
--- a/contrib/VS2005/zstd/zstd.vcproj
+++ b/contrib/VS2005/zstd/zstd.vcproj
@@ -44,7 +44,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\lib\dictBuilder;$(SolutionDir)..\..\lib\compress"
-				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=4;WIN32;_DEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=0;WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
@@ -121,7 +121,7 @@
 				EnableIntrinsicFunctions="true"
 				OmitFramePointers="true"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\lib\dictBuilder;$(SolutionDir)..\..\lib\compress"
-				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=4;WIN32;NDEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=0;WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				EnableFunctionLevelLinking="true"
 				UsePrecompiledHeader="0"
@@ -196,7 +196,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\lib\dictBuilder;$(SolutionDir)..\..\lib\compress"
-				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=4;WIN32;_DEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=0;WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
@@ -274,7 +274,7 @@
 				EnableIntrinsicFunctions="true"
 				OmitFramePointers="true"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\lib\dictBuilder;$(SolutionDir)..\..\lib\compress"
-				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=4;WIN32;NDEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=0;WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				EnableFunctionLevelLinking="true"
 				UsePrecompiledHeader="0"
diff --git a/contrib/VS2005/zstdlib/zstdlib.vcproj b/contrib/VS2005/zstdlib/zstdlib.vcproj
index 67ddd2dba3a..e5e98d14f0e 100644
--- a/contrib/VS2005/zstdlib/zstdlib.vcproj
+++ b/contrib/VS2005/zstdlib/zstdlib.vcproj
@@ -44,7 +44,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs\legacy;$(SolutionDir)..\..\lib\dictBuilder"
-				PreprocessorDefinitions="ZSTD_DLL_EXPORT=1;ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=4;WIN32;_DEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_DLL_EXPORT=1;ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=0;WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
@@ -120,7 +120,7 @@
 				EnableIntrinsicFunctions="true"
 				OmitFramePointers="true"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs\legacy;$(SolutionDir)..\..\lib\dictBuilder"
-				PreprocessorDefinitions="ZSTD_DLL_EXPORT=1;ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=4;WIN32;NDEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_DLL_EXPORT=1;ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=0;WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				EnableFunctionLevelLinking="true"
 				UsePrecompiledHeader="0"
@@ -194,7 +194,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs\legacy;$(SolutionDir)..\..\lib\dictBuilder"
-				PreprocessorDefinitions="ZSTD_DLL_EXPORT=1;ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=4;WIN32;_DEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_DLL_EXPORT=1;ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=0;WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
@@ -271,7 +271,7 @@
 				EnableIntrinsicFunctions="true"
 				OmitFramePointers="true"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs\legacy;$(SolutionDir)..\..\lib\dictBuilder"
-				PreprocessorDefinitions="ZSTD_DLL_EXPORT=1;ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=4;WIN32;NDEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_DLL_EXPORT=1;ZSTD_MULTITHREAD=1;ZSTD_LEGACY_SUPPORT=0;WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				EnableFunctionLevelLinking="true"
 				UsePrecompiledHeader="0"
diff --git a/lib/BUCK b/lib/BUCK
index 8c555a8be18..5d10cfa10db 100644
--- a/lib/BUCK
+++ b/lib/BUCK
@@ -32,7 +32,6 @@ cxx_library(
     srcs=glob(['decompress/zstd*.c']),
     deps=[
         ':common',
-        ':legacy',
     ],
 )
 
@@ -47,6 +46,14 @@ cxx_library(
     deps=[':common'],
 )
 
+# Decoders for formats older than v0.8. Not a dependency of :decompress,
+# because ZSTD_LEGACY_SUPPORT is 0 (see .buckconfig), which makes them
+# unreachable.
+# Enabling legacy formats means two edits, which only make sense together :
+# raise the level in .buckconfig, AND add ':legacy' to :decompress deps.
+# Raising the level alone fails to link, which is easy to notice. Adding the
+# dep alone is silent : these decoders get compiled back in, while
+# ZSTD_isLegacy() remains compiled out, so legacy frames are still rejected.
 cxx_library(
     name='legacy',
     header_namespace='',
@@ -56,9 +63,6 @@ cxx_library(
     ]),
     srcs=glob(['legacy/*.c']),
     deps=[':common'],
-    exported_preprocessor_flags=[
-        '-DZSTD_LEGACY_SUPPORT=0',
-    ],
 )
 
 cxx_library(
@@ -132,7 +136,7 @@ cxx_library(
     exported_headers=[
         'zstd_errors.h',
         'common/error_private.h',
-    ]
+    ],
     srcs=['common/error_private.c'],
 )
 
diff --git a/programs/README.md b/programs/README.md
index 6522b647dd3..268bdc52357 100644
--- a/programs/README.md
+++ b/programs/README.md
@@ -3,8 +3,8 @@ Command Line Interface for Zstandard library
 
 Command Line Interface (CLI) can be created using the `make` command without any additional parameters.
 There are however other Makefile targets that create different variations of CLI:
-- `zstd` : default CLI supporting gzip-like arguments; includes dictionary builder, benchmark, and supports decompression of legacy zstd formats
-- `zstd_nolegacy` : Same as `zstd` but without support for legacy zstd formats
+- `zstd` : default CLI supporting gzip-like arguments; includes dictionary builder and benchmark
+- `zstd_nolegacy` : Same as `zstd` but with support for legacy zstd formats explicitly disabled
 - `zstd-small` : CLI optimized for minimal size; no dictionary builder, no benchmark, and no support for legacy zstd formats
 - `zstd-compress` : version of CLI which can only compress into zstd format
 - `zstd-decompress` : version of CLI which can only decompress zstd format
@@ -23,11 +23,12 @@ There are however other Makefile targets that create different variations of CLI
 - __ZSTD_LEGACY_SUPPORT__ : `zstd` can decompress files compressed by older versions of `zstd`.
   Starting v0.8.0, all versions of `zstd` produce frames compliant with the [specification](../doc/zstd_compression_format.md), and are therefore compatible.
   But older versions (< v0.8.0) produced different, incompatible, frames.
-  By default, `zstd` supports decoding legacy formats >= v0.4.0 (`ZSTD_LEGACY_SUPPORT=4`).
+  Since v1.6.0, legacy format support is disabled by default (`ZSTD_LEGACY_SUPPORT=0`).
   This can be altered by modifying this compilation variable.
   `ZSTD_LEGACY_SUPPORT=1` means "support all formats >= v0.1.0".
   `ZSTD_LEGACY_SUPPORT=2` means "support all formats >= v0.2.0", and so on.
   `ZSTD_LEGACY_SUPPORT=0` means _DO NOT_ support any legacy format.
+  Example : `make zstd ZSTD_LEGACY_SUPPORT=4`
   if `ZSTD_LEGACY_SUPPORT >= 8`, it's the same as `0`, since there is no legacy format after `7`.
   Note : `zstd` only supports decoding older formats, and cannot generate any legacy format.
 
diff --git a/tests/Makefile b/tests/Makefile
index bfa796ba05b..e268ddeb9e4 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -44,8 +44,12 @@ CPPFLAGS   += -I$(LIB_SRCDIR) -I$(LIB_SRCDIR)/common -I$(LIB_SRCDIR)/compress -I
 ZSTDCOMMON_FILES := $(sort $(ZSTD_COMMON_FILES))
 ZSTDCOMP_FILES   := $(sort $(ZSTD_COMPRESS_FILES))
 ZSTDDECOMP_FILES := $(sort $(ZSTD_DECOMPRESS_FILES))
-ZSTDLEGACY_FILES := $(sort $(wildcard $(LIB_SRCDIR)/legacy/*.c))
-ZSTD_FILES  := $(ZSTDDECOMP_FILES) $(ZSTDCOMMON_FILES) $(ZSTDCOMP_FILES) $(ZSTDLEGACY_FILES)
+# every decoder, whatever ZSTD_LEGACY_SUPPORT : only the `legacy` target wants these
+ALL_LEGACY_FILES := $(sort $(wildcard $(LIB_SRCDIR)/legacy/*.c))
+# ZSTD_LEGACY_FILES (from libzstd.mk) is the subset selected for the requested
+# level. It's empty when legacy support is disabled, hence unreachable decoders
+# are not compiled into the test binaries.
+ZSTD_FILES  := $(ZSTDDECOMP_FILES) $(ZSTDCOMMON_FILES) $(ZSTDCOMP_FILES) $(sort $(ZSTD_LEGACY_FILES))
 ZDICT_FILES := $(sort $(ZSTD_DICTBUILDER_FILES))
 
 ZSTD_F1 := $(sort $(wildcard $(ZSTD_FILES)))
@@ -233,8 +237,11 @@ CLEAN += invalidDictionaries
 invalidDictionaries : $(ZSTD_OBJECTS) invalidDictionaries.c
 
 CLEAN += legacy
-legacy : CPPFLAGS += -UZSTD_LEGACY_SUPPORT -DZSTD_LEGACY_SUPPORT=4
-legacy : $(ZSTD_FILES) legacy.c
+# legacy.c adapts to the level it is compiled with : it only tests the frames
+# this level can decode. Default to the oldest format, to cover all decoders.
+LEGACY_TEST_LEVEL ?= 1
+legacy : CPPFLAGS += -UZSTD_LEGACY_SUPPORT -DZSTD_LEGACY_SUPPORT=$(LEGACY_TEST_LEVEL)
+legacy : $(ZSTD_FILES) $(ALL_LEGACY_FILES) legacy.c
 
 CLEAN += decodecorpus
 decodecorpus : LDLIBS += -lm
diff --git a/tests/fuzz/Makefile b/tests/fuzz/Makefile
index 13e29bb7a96..1141c51265c 100644
--- a/tests/fuzz/Makefile
+++ b/tests/fuzz/Makefile
@@ -26,6 +26,7 @@ CORPORA_URL_PREFIX:=https://github.com/facebook/zstd/releases/download/fuzz-corp
 
 LIBZSTD_MK_DIR = ../../lib
 DEBUGLEVEL ?= 2
+# fuzzers keep legacy decoders enabled, they are still built on demand
 ZSTD_LEGACY_SUPPORT ?= 1
 
 .PHONY: default
@@ -40,10 +41,14 @@ DEFAULT_SEQ_PROD_DIR = $(CONTRIBDIR)/externalSequenceProducer
 DEFAULT_SEQ_PROD_SRC = $(DEFAULT_SEQ_PROD_DIR)/sequence_producer.c
 THIRD_PARTY_SEQ_PROD_OBJ ?=
 
+# Note : ZSTD_LEGACY_SUPPORT below looks redundant with libzstd.mk, which adds
+# the same define to CPPFLAGS. It is not : fuzz.py passes CPPFLAGS on the make
+# command line, and that overrides the `CPPFLAGS +=` there. Dropping it silently
+# disables the legacy decoders in every OSS-Fuzz and regressiontest build.
 FUZZ_CPPFLAGS := -I$(LIB_SRCDIR) -I$(LIB_SRCDIR)/common -I$(LIB_SRCDIR)/compress \
 	-I$(LIB_SRCDIR)/dictBuilder -I$(LIB_SRCDIR)/deprecated -I$(LIB_SRCDIR)/legacy \
 	-I$(CONTRIBDIR)/seekable_format -I$(PRGDIR) -I$(DEFAULT_SEQ_PROD_DIR) \
-	-DZSTD_MULTITHREAD -DZSTD_LEGACY_SUPPORT=1 $(CPPFLAGS)
+	-DZSTD_MULTITHREAD -DZSTD_LEGACY_SUPPORT=$(ZSTD_LEGACY_SUPPORT) $(CPPFLAGS)
 FUZZ_EXTRA_FLAGS := -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
 	-Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
 	-Wstrict-prototypes -Wundef \
diff --git a/tests/legacy.c b/tests/legacy.c
index 8fe291c5a0d..18a590f1d51 100644
--- a/tests/legacy.c
+++ b/tests/legacy.c
@@ -19,11 +19,18 @@
 #include <stddef.h>              /* size_t */
 #include <stdlib.h>              /* malloc, free */
 #include <stdio.h>               /* fprintf */
-#include <string.h>              /* strlen */
+#include <string.h>              /* strlen, memcpy, memcmp */
 #define ZSTD_STATIC_LINKING_ONLY /* ZSTD_decompressBound */
 #include "zstd.h"
 #include "zstd_errors.h"
 
+/* Same normalization as lib/legacy/zstd_legacy.h :
+ * no legacy support means only the current format can be decoded */
+#if !defined(ZSTD_LEGACY_SUPPORT) || (ZSTD_LEGACY_SUPPORT == 0)
+#  undef ZSTD_LEGACY_SUPPORT
+#  define ZSTD_LEGACY_SUPPORT 8
+#endif
+
 /*===========================================
 *   Macros
 *==========================================*/
@@ -32,15 +39,87 @@
 /*===========================================
 *   Precompressed frames
 *==========================================*/
-const char* const COMPRESSED; /* content is at end of file */
-size_t const COMPRESSED_SIZE = 917;
-const char* const EXPECTED; /* content is at end of file */
+/* Each frame below is the "BLOCK" text, compressed with default settings by
+ * the last release able to produce that format version.
+ * A frame produced by v0.N is only decodable when ZSTD_LEGACY_SUPPORT <= N,
+ * hence the test adapts itself to the level it has been compiled with.
+ */
+#define FRAME_V01_SIZE 189
+#define FRAME_V02_SIZE 187
+#define FRAME_V03_SIZE 187
+#define FRAME_V04_SIZE 198
+#define FRAME_V05_SIZE 184
+#define FRAME_V06_SIZE 178
+#define FRAME_V07_SIZE 178
+#define FRAME_V08_SIZE 179
+#define ALL_FRAMES_SIZE (FRAME_V01_SIZE + FRAME_V02_SIZE + FRAME_V03_SIZE + FRAME_V04_SIZE + FRAME_V05_SIZE + FRAME_V06_SIZE + FRAME_V07_SIZE + FRAME_V08_SIZE)
+
+const char* const FRAME_V01;   /* content is at end of file, produced by v0.1.1 */
+const char* const FRAME_V02;   /* content is at end of file, produced by v0.2.2 */
+const char* const FRAME_V03;   /* content is at end of file, produced by v0.3.6 */
+const char* const FRAME_V04;   /* content is at end of file, produced by v0.4.3 */
+const char* const FRAME_V05;   /* content is at end of file, produced by v0.5.0 */
+const char* const FRAME_V06;   /* content is at end of file, produced by v0.6.0 */
+const char* const FRAME_V07;   /* content is at end of file, produced by v0.7.0 */
+const char* const FRAME_V08;   /* content is at end of file, produced by v0.8.0 */
+const char* const BLOCK;      /* content is at end of file */
+
 
+/* legacy formats older than v0.4 only offer a single-shot decoder :
+ * ZSTD_decompressStream() answers version_unsupported on such frames
+ * (see ZSTD_initLegacyStream() in lib/legacy/zstd_legacy.h) */
+#define OLDEST_STREAMABLE_VERSION 4
 
-static int testSimpleAPI(void)
+/* buildTestFrames() :
+ * concatenates, oldest first, the frames this build is able to decode,
+ * skipping those older than @fromVersion.
+ * @dst must be at least ALL_FRAMES_SIZE bytes long.
+ * @return : nb of frames written; *cSize receives their total size */
+static unsigned buildTestFrames(char* dst, size_t* cSize, int fromVersion)
 {
-    size_t const size = strlen(EXPECTED);
-    char* const output = malloc(size);
+    unsigned nbFrames = 0;
+    size_t pos = 0;
+
+#define ADD_FRAME(n, v)                                     \
+    if (fromVersion <= (n)) {                               \
+        memcpy(dst + pos, FRAME_V##v, FRAME_V##v##_SIZE);   \
+        pos += FRAME_V##v##_SIZE;                           \
+        nbFrames++;                                         \
+    }
+
+#if (ZSTD_LEGACY_SUPPORT <= 1)
+    ADD_FRAME(1, 01)
+#endif
+#if (ZSTD_LEGACY_SUPPORT <= 2)
+    ADD_FRAME(2, 02)
+#endif
+#if (ZSTD_LEGACY_SUPPORT <= 3)
+    ADD_FRAME(3, 03)
+#endif
+#if (ZSTD_LEGACY_SUPPORT <= 4)
+    ADD_FRAME(4, 04)
+#endif
+#if (ZSTD_LEGACY_SUPPORT <= 5)
+    ADD_FRAME(5, 05)
+#endif
+#if (ZSTD_LEGACY_SUPPORT <= 6)
+    ADD_FRAME(6, 06)
+#endif
+#if (ZSTD_LEGACY_SUPPORT <= 7)
+    ADD_FRAME(7, 07)
+#endif
+    ADD_FRAME(8, 08)
+#undef ADD_FRAME
+
+    *cSize = pos;
+    return nbFrames;
+}
+
+
+static int testSimpleAPI(const char* compressed, size_t compressedSize,
+                         const char* expected, size_t expectedSize)
+{
+    char* const output = malloc(expectedSize);
 
     if (!output) {
         DISPLAY("ERROR: Not enough memory!\n");
@@ -48,7 +127,7 @@ static int testSimpleAPI(void)
     }
 
     {
-        size_t const ret = ZSTD_decompress(output, size, COMPRESSED, COMPRESSED_SIZE);
+        size_t const ret = ZSTD_decompress(output, expectedSize, compressed, compressedSize);
         if (ZSTD_isError(ret)) {
             if (ret == ZSTD_error_prefix_unknown) {
                 DISPLAY("ERROR: Invalid frame magic number, was this compiled "
@@ -59,11 +138,13 @@ static int testSimpleAPI(void)
             free(output);
             return 1;
         }
-        if (ret != size) {
+        if (ret != expectedSize) {
             DISPLAY("ERROR: Wrong decoded size\n");
+            free(output);
+            return 1;
         }
     }
-    if (memcmp(EXPECTED, output, size) != 0) {
+    if (memcmp(expected, output, expectedSize) != 0) {
         DISPLAY("ERROR: Wrong decoded output produced\n");
         free(output);
         return 1;
@@ -75,16 +156,20 @@ static int testSimpleAPI(void)
 }
 
 
-static int testStreamingAPI(void)
+static int testStreamingAPI(const char* compressed, size_t compressedSize,
+                            const char* expected, size_t expectedSize)
 {
     int error_code = 0;
     size_t const outBuffSize = ZSTD_DStreamOutSize();
     char* const outBuff = malloc(outBuffSize);
     ZSTD_DStream* const stream = ZSTD_createDStream();
-    ZSTD_inBuffer input = { COMPRESSED, COMPRESSED_SIZE, 0 };
+    ZSTD_inBuffer input = { NULL, 0, 0 };
     size_t outputPos = 0;
     int needsInit = 1;
 
+    input.src = compressed;
+    input.size = compressedSize;
+
     if (outBuff == NULL) {
         DISPLAY("ERROR: Could not allocate memory\n");
         return 1;
@@ -116,7 +201,12 @@ static int testStreamingAPI(void)
                 needsInit = 1;
         }   }
 
-        if (memcmp(outBuff, EXPECTED + outputPos, output.pos) != 0) {
+        if (outputPos + output.pos > expectedSize) {
+            DISPLAY("ERROR: Decoded more than expected\n");
+            error_code = 1;
+            break;
+        }
+        if (memcmp(outBuff, expected + outputPos, output.pos) != 0) {
             DISPLAY("ERROR: Wrong decoded output produced\n");
             error_code = 1;
             break;
@@ -127,20 +217,26 @@ static int testStreamingAPI(void)
         }
     }
 
+    if (error_code == 0 && outputPos != expectedSize) {
+        DISPLAY("ERROR: Decoded less than expected\n");
+        error_code = 1;
+    }
+
     free(outBuff);
     ZSTD_freeDStream(stream);
     if (error_code == 0) DISPLAY("Streaming API OK\n");
     return error_code;
 }
 
-static int testFrameDecoding(void)
+static int testFrameDecoding(const char* compressed, size_t compressedSize,
+                             size_t expectedSize)
 {
-    if (strlen(EXPECTED) > ZSTD_decompressBound(COMPRESSED, COMPRESSED_SIZE)) {
+    if (expectedSize > ZSTD_decompressBound(compressed, compressedSize)) {
         DISPLAY("ERROR: ZSTD_decompressBound: decompressed bound too small\n");
         return 1;
     }
-    {   const char* ip = COMPRESSED;
-        size_t remainingSize = COMPRESSED_SIZE;
+    {   const char* ip = compressed;
+        size_t remainingSize = compressedSize;
         while (1) {
             size_t frameSize = ZSTD_findFrameCompressedSize(ip, remainingSize);
             if (ZSTD_isError(frameSize)) {
@@ -162,25 +258,99 @@ static int testFrameDecoding(void)
 
 int main(void)
 {
-    {   int const ret = testSimpleAPI();
-        if (ret) return ret; }
-    {   int const ret = testStreamingAPI();
-        if (ret) return ret; }
-    {   int const ret = testFrameDecoding();
-        if (ret) return ret; }
-
-    DISPLAY("OK\n");
-    return 0;
+    size_t const blockSize = strlen(BLOCK);
+    char* const compressed = malloc(ALL_FRAMES_SIZE);
+    /* the streaming API can only replay the subset of frames for which a
+     * legacy streaming decoder exists : it gets a buffer of its own, so that
+     * each buffer keeps matching the size recorded next to it */
+    char* const streamable = malloc(ALL_FRAMES_SIZE);
+    char* expected = NULL;
+    size_t compressedSize = 0;
+    size_t streamableSize = 0;
+    size_t expectedSize = 0;
+    unsigned nbFrames = 0;
+    unsigned nbStreamFrames = 0;
+    int result = 1;
+
+    do {
+        if (compressed == NULL || streamable == NULL) {
+            DISPLAY("ERROR: Not enough memory!\n");
+            break;
+        }
+        nbFrames = buildTestFrames(compressed, &compressedSize, 1);
+        nbStreamFrames = buildTestFrames(streamable, &streamableSize, OLDEST_STREAMABLE_VERSION);
+        DISPLAY("Testing %u frames, from format v0.%i upward\n", nbFrames, ZSTD_LEGACY_SUPPORT);
+
+        expectedSize = blockSize * nbFrames;
+        expected = malloc(expectedSize);
+        if (expected == NULL) {
+            DISPLAY("ERROR: Not enough memory!\n");
+            break;
+        }
+        {   unsigned u;
+            for (u = 0; u < nbFrames; u++)
+                memcpy(expected + (u * blockSize), BLOCK, blockSize);
+        }
+
+        if (testSimpleAPI(compressed, compressedSize, expected, expectedSize)) break;
+        if (testFrameDecoding(compressed, compressedSize, expectedSize)) break;
+        /* all blocks being identical, the first @nbStreamFrames ones
+         * are what the streaming subset must decode to */
+        if (testStreamingAPI(streamable, streamableSize,
+                             expected, blockSize * nbStreamFrames)) break;
+        result = 0;
+    } while (0);
+
+    free(expected);
+    free(streamable);
+    free(compressed);
+    if (result == 0) DISPLAY("OK\n");
+    return result;
 }
 
-/* Consists of the "EXPECTED" string compressed with default settings on
-    - v0.4.3
-    - v0.5.0
-    - v0.6.0
-    - v0.7.0
-    - v0.8.0
-*/
-const char* const COMPRESSED =
+const char* const FRAME_V01 =
+    "\xFD\x2F\xB5\x1E\x00\x00\xB3\x00\x00\x9D\x00\xD8\x1F\xB0\x01\x10"
+    "\x00\x00\x00\xA0\xCA\x4C\xCF\x43\xDF\xF9\xF8\x7B\x7F\xFE\x3F\xDF"
+    "\xDD\xDF\xC3\x86\x55\x63\x3A\x68\x70\x44\x44\x08\x1F\x00\x1D\x00"
+    "\x1D\x00\x44\x21\x80\x32\xAD\x75\x6F\xB1\x6B\x3B\x7A\x3F\x77\xAE"
+    "\x8F\x95\x4A\x73\xEC\xCF\x73\x0C\x07\x9A\x9E\xF0\x5E\xB4\xCB\x94"
+    "\x06\x99\xE6\x3E\x28\xF0\x80\x42\xA9\x1A\x2B\x0E\xDF\xC9\x06\x82"
+    "\xB6\x56\x72\x98\x49\xB2\xBE\xEE\xCD\x25\xA1\xAC\x86\x01\x99\xD4"
+    "\x28\x05\x9F\xC8\xF9\x1D\x90\x30\x6B\x18\x08\x9B\xA0\xF5\x12\xC9"
+    "\x5F\x4B\x80\x37\xAD\x14\x5A\xD2\xCD\x98\x01\xE8\x77\x03\x63\x08"
+    "\xB4\xA4\x81\xD8\xE9\x24\xB2\x73\x9F\x9C\x03\x07\x52\x6A\x2F\xC2"
+    "\xCE\x70\x1B\xFF\xD0\x4E\x01\x04\x00\x54\x01\x43\x80\x07\x00\xA1"
+    "\x28\x3F\x20\x9C\x6A\x30\xA3\x01\xC8\x12\xC0\x00\x00";
+
+const char* const FRAME_V02 =
+    "\x22\xB5\x2F\xFD\x00\x00\xB1\x60\x03\x20\x13\x00\x1F\xB0\x01\x10"
+    "\x00\x00\x00\xA0\xCA\x4C\xCF\x43\xDF\xF9\xF8\x7B\x7F\xFE\x3F\xDF"
+    "\xDD\xDF\xC3\x86\x55\x63\x3A\x68\x70\x44\x44\x08\x19\x00\x1D\x00"
+    "\x1E\x00\xAB\x65\x8D\x76\xE9\x32\x5A\x7D\xA3\x19\xED\xF6\x94\xB8"
+    "\x12\xEC\x2E\xA3\xB9\x6C\x35\xA3\x55\x4A\xD4\xC9\x68\x56\x3B\x79"
+    "\xDB\x40\xEA\x07\x52\x23\x99\x5C\x3E\xB2\xB6\xB3\x6B\xCE\x96\x18"
+    "\x2A\xF3\x20\x00\x0A\xED\xED\x36\xB5\xB1\x2E\x72\xBA\x1D\xCC\x19"
+    "\xED\x12\x51\x9C\x63\x0E\xE7\x5E\xC8\xB8\xCD\xF0\x39\x84\xC4\x6E"
+    "\x2F\x27\x46\x8D\x90\x0C\x44\x21\x80\x32\xAD\x28\xB3\x4E\x79\xAB"
+    "\x79\x8D\xDB\xCB\x85\x41\xC1\xC1\x9A\x8B\x35\xA3\x11\xE4\xAB\x48"
+    "\xC0\xE5\x02\xCA\x0C\x04\x00\x54\x01\x43\x80\x07\x00\xA1\x28\x3F"
+    "\x20\x9C\x6A\x30\xA3\x01\xC8\x12\xC0\x00\x00";
+
+const char* const FRAME_V03 =
+    "\x23\xB5\x2F\xFD\x00\x00\xB1\x50\x03\xE0\x12\x00\x1F\xB0\x01\x10"
+    "\x00\x00\x00\xA0\xCA\x4C\xCF\x43\xDF\xF9\xF8\x7B\x7F\xFE\x3F\xDF"
+    "\xDD\xDF\xC3\x86\x55\x63\x3A\x68\x70\x44\x44\x08\x19\x00\x1D\x00"
+    "\x1D\x00\x6A\x59\xA3\x5D\xBA\x8C\x56\xDF\x68\x46\xBB\x3D\x25\xAE"
+    "\x04\xBB\xCB\x68\x2E\x5B\xCD\x68\x95\x12\x35\x48\x26\xA3\x59\xED"
+    "\xE4\x6D\x03\xA9\x1F\x48\x8D\x64\x72\xF9\xC8\xDA\xCE\xAE\x39\x5B"
+    "\x62\xA8\xCC\x83\x00\x28\xB4\x0F\x59\x1B\xEB\x22\xA7\xDB\xC1\x9C"
+    "\xD1\x2E\x11\xC5\x39\xE6\x70\xEE\x85\x8C\xDB\x0C\x9F\x43\x48\xEC"
+    "\xF6\x72\x62\xD4\x28\x44\x21\x80\x32\xAD\x28\xB3\x4E\x79\xAB\x79"
+    "\x8D\xDB\xCB\x85\x41\xC1\xC1\x9A\x8B\x35\xA3\x11\xE4\xAB\x48\xC0"
+    "\xE5\x02\xCA\x05\x00\x54\x01\x43\x80\x07\x00\xA1\x28\x3F\xE0\x04"
+    "\x80\x00\xA0\xC1\x8C\x06\x20\x4B\xC0\x00\x00";
+
+const char* const FRAME_V04 =
     "\x24\xB5\x2F\xFD\x00\x00\x00\xBB\xB0\x02\xC0\x10\x00\x1E\xB0\x01"
     "\x02\x00\x00\x80\x00\xE8\x92\x34\x12\x97\xC8\xDF\xE9\xF3\xEF\x53"
     "\xEA\x1D\x27\x4F\x0C\x44\x90\x0C\x8D\xF1\xB4\x89\x17\x00\x18\x00"
@@ -193,29 +363,37 @@ const char* const COMPRESSED =
     "\xC6\xBA\x01\x0E\x00\x54\x00\x00\x19\x00\x00\x54\x14\x00\x24\x24"
     "\x04\xFE\x04\x84\x4E\x41\x00\x27\xE2\x02\xC4\xB1\x00\xD2\x51\x00"
     "\x79\x58\x41\x28\x00\xE0\x0C\x01\x68\x65\x00\x04\x13\x0C\xDA\x0C"
-    "\x80\x22\x06\xC0\x00\x00\x25\xB5\x2F\xFD\x00\x00\x00\xAD\x12\xB0"
-    "\x7D\x1E\xB0\x01\x02\x00\x00\x80\x00\xE8\x92\x34\x12\x97\xC8\xDF"
-    "\xE9\xF3\xEF\x53\xEA\x1D\x27\x4F\x0C\x44\x90\x0C\x8D\xF1\xB4\x89"
-    "\x03\x01\x50\x67\x56\xF5\x9F\x35\x84\x60\xA0\x60\x91\xC9\x0A\xDC"
-    "\xAB\xAB\xE0\xE2\x81\xFA\xCF\xC6\xBA\xEB\xA8\xD1\x40\x39\x90\x4C"
-    "\x64\xF8\xEB\x53\xE6\x18\x0B\x67\x12\xAD\xB8\x99\xB3\x5A\x6F\x8A"
-    "\xF9\x63\x0C\xB8\xFA\x58\xE7\xF5\xE6\xE2\xE3\x67\xCC\x5D\x94\xC6"
-    "\x56\xDC\x7F\x0C\x84\x4B\xA8\xF8\x63\x2E\x3E\x4E\x67\xCD\x9E\xAC"
-    "\x04\x1E\x17\x27\xE4\x43\xF6\xA4\x56\xE4\x84\xC7\x9E\x34\x0E\x00"
-    "\x00\x32\x40\x80\xA8\x00\x01\x49\x81\xE0\x3C\x01\x29\x1D\x00\x87"
-    "\xCE\x80\x75\x08\x80\x72\x24\x00\x7B\x52\x00\x94\x00\x20\xCC\x01"
-    "\x86\xD2\x00\x81\x09\x83\xC1\x34\xA0\x88\x01\xC0\x00\x00\x26\xB5"
-    "\x2F\xFD\x42\xEF\x00\x00\xA6\x12\xB0\x7D\x1E\xB0\x01\x02\x00\x00"
-    "\x54\xA0\xBA\x24\x8D\xC4\x25\xF2\x77\xFA\xFC\xFB\x94\x7A\xC7\xC9"
-    "\x13\x03\x11\x24\x43\x63\x3C\x6D\x22\x03\x01\x50\x67\x56\xF5\x9F"
-    "\x35\x84\x60\xA0\x60\x91\xC9\x0A\xDC\xAB\xAB\xE0\xE2\x81\xFA\xCF"
-    "\xC6\xBA\xEB\xA8\xD1\x40\x39\x90\x4C\x64\xF8\xEB\x53\xE6\x18\x0B"
-    "\x67\x12\xAD\xB8\x99\xB3\x5A\x6F\x8A\xF9\x63\x0C\xB8\xFA\x58\xE7"
-    "\xF5\xE6\xE2\xE3\x67\xCC\x5D\x94\xC6\x56\xDC\x7F\x0C\x84\x4B\xA8"
-    "\xF8\x63\x2E\x3E\x4E\x67\xCD\x9E\xAC\x04\x1E\x17\x27\xE4\x43\xF6"
-    "\xA4\x56\xE4\x84\xC7\x9E\x34\x0E\x00\x35\x0B\x71\xB5\xC0\x2A\x5C"
-    "\x26\x94\x22\x20\x8B\x4C\x8D\x13\x47\x58\x67\x15\x6C\xF1\x1C\x4B"
-    "\x54\x10\x9D\x31\x50\x85\x4B\x54\x0E\x01\x4B\x3D\x01\xC0\x00\x00"
+    "\x80\x22\x06\xC0\x00\x00";
+
+const char* const FRAME_V05 =
+    "\x25\xB5\x2F\xFD\x00\x00\x00\xAD\x12\xB0\x7D\x1E\xB0\x01\x02\x00"
+    "\x00\x80\x00\xE8\x92\x34\x12\x97\xC8\xDF\xE9\xF3\xEF\x53\xEA\x1D"
+    "\x27\x4F\x0C\x44\x90\x0C\x8D\xF1\xB4\x89\x03\x01\x50\x67\x56\xF5"
+    "\x9F\x35\x84\x60\xA0\x60\x91\xC9\x0A\xDC\xAB\xAB\xE0\xE2\x81\xFA"
+    "\xCF\xC6\xBA\xEB\xA8\xD1\x40\x39\x90\x4C\x64\xF8\xEB\x53\xE6\x18"
+    "\x0B\x67\x12\xAD\xB8\x99\xB3\x5A\x6F\x8A\xF9\x63\x0C\xB8\xFA\x58"
+    "\xE7\xF5\xE6\xE2\xE3\x67\xCC\x5D\x94\xC6\x56\xDC\x7F\x0C\x84\x4B"
+    "\xA8\xF8\x63\x2E\x3E\x4E\x67\xCD\x9E\xAC\x04\x1E\x17\x27\xE4\x43"
+    "\xF6\xA4\x56\xE4\x84\xC7\x9E\x34\x0E\x00\x00\x32\x40\x80\xA8\x00"
+    "\x01\x49\x81\xE0\x3C\x01\x29\x1D\x00\x87\xCE\x80\x75\x08\x80\x72"
+    "\x24\x00\x7B\x52\x00\x94\x00\x20\xCC\x01\x86\xD2\x00\x81\x09\x83"
+    "\xC1\x34\xA0\x88\x01\xC0\x00\x00";
+
+const char* const FRAME_V06 =
+    "\x26\xB5\x2F\xFD\x42\xEF\x00\x00\xA6\x12\xB0\x7D\x1E\xB0\x01\x02"
+    "\x00\x00\x54\xA0\xBA\x24\x8D\xC4\x25\xF2\x77\xFA\xFC\xFB\x94\x7A"
+    "\xC7\xC9\x13\x03\x11\x24\x43\x63\x3C\x6D\x22\x03\x01\x50\x67\x56"
+    "\xF5\x9F\x35\x84\x60\xA0\x60\x91\xC9\x0A\xDC\xAB\xAB\xE0\xE2\x81"
+    "\xFA\xCF\xC6\xBA\xEB\xA8\xD1\x40\x39\x90\x4C\x64\xF8\xEB\x53\xE6"
+    "\x18\x0B\x67\x12\xAD\xB8\x99\xB3\x5A\x6F\x8A\xF9\x63\x0C\xB8\xFA"
+    "\x58\xE7\xF5\xE6\xE2\xE3\x67\xCC\x5D\x94\xC6\x56\xDC\x7F\x0C\x84"
+    "\x4B\xA8\xF8\x63\x2E\x3E\x4E\x67\xCD\x9E\xAC\x04\x1E\x17\x27\xE4"
+    "\x43\xF6\xA4\x56\xE4\x84\xC7\x9E\x34\x0E\x00\x35\x0B\x71\xB5\xC0"
+    "\x2A\x5C\x26\x94\x22\x20\x8B\x4C\x8D\x13\x47\x58\x67\x15\x6C\xF1"
+    "\x1C\x4B\x54\x10\x9D\x31\x50\x85\x4B\x54\x0E\x01\x4B\x3D\x01\xC0"
+    "\x00\x00";
+
+const char* const FRAME_V07 =
     "\x27\xB5\x2F\xFD\x20\xEF\x00\x00\xA6\x12\xE4\x84\x1F\xB0\x01\x10"
     "\x00\x00\x00\x35\x59\xA6\xE7\xA1\xEF\x7C\xFC\xBD\x3F\xFF\x9F\xEF"
     "\xEE\xEF\x61\xC3\xAA\x31\x1D\x34\x38\x22\x22\x04\x44\x21\x80\x32"
@@ -227,36 +405,24 @@ const char* const COMPRESSED =
     "\x7B\x4A\x5C\x09\x76\x97\xD1\x5C\x96\x12\x75\x35\xA3\x55\x4A\xD4"
     "\x0B\x00\x35\x0B\x71\xB5\xC0\x2A\x5C\xE6\x08\x45\xF1\x39\x43\xF1"
     "\x1C\x4B\x54\x10\x9D\x31\x50\x85\x4B\x54\x0E\x01\x4B\x3D\x01\xC0"
-    "\x00\x00\x28\xB5\x2F\xFD\x24\xEF\x35\x05\x00\x92\x0B\x21\x1F\xB0"
-    "\x01\x10\x00\x00\x00\x35\x59\xA6\xE7\xA1\xEF\x7C\xFC\xBD\x3F\xFF"
-    "\x9F\xEF\xEE\xEF\x61\xC3\xAA\x31\x1D\x34\x38\x22\x22\x04\x44\x21"
-    "\x80\x32\xAD\x28\xF3\xD6\x28\x0C\x0A\x0E\xD6\x5C\xAC\x19\x8D\x20"
-    "\x5F\x45\x02\x2E\x17\x50\x66\x6D\xAC\x8B\x9C\x6E\x07\x73\x46\xBB"
-    "\x44\x14\xE7\x98\xC3\xB9\x17\x32\x6E\x33\x7C\x0E\x21\xB1\xDB\xCB"
-    "\x89\x51\x23\x34\xAB\x9D\xBC\x6D\x20\xF5\x03\xA9\x91\x4C\x2E\x1F"
-    "\x59\xDB\xD9\x35\x67\x4B\x0C\x95\x79\x10\x00\x85\xA6\x96\x95\x2E"
-    "\xDF\x78\x7B\x4A\x5C\x09\x76\x97\xD1\x5C\x96\x12\x75\x35\xA3\x55"
-    "\x4A\xD4\x0B\x00\x35\x0B\x71\xB5\xC0\x2A\x5C\xE6\x08\x45\xF1\x39"
-    "\x43\xF1\x1C\x4B\x54\x10\x9D\x31\x50\x85\x4B\x54\x0E\x01\x4B\x3D"
-    "\x01\xD2\x2F\x21\x80";
-
-const char* const EXPECTED =
-    "snowden is snowed in / he's now then in his snow den / when does the snow end?\n"
-    "goodbye little dog / you dug some holes in your day / they'll be hard to fill.\n"
-    "when life shuts a door, / just open it. it’s a door. / that is how doors work.\n"
-
-    "snowden is snowed in / he's now then in his snow den / when does the snow end?\n"
-    "goodbye little dog / you dug some holes in your day / they'll be hard to fill.\n"
-    "when life shuts a door, / just open it. it’s a door. / that is how doors work.\n"
+    "\x00\x00";
 
-    "snowden is snowed in / he's now then in his snow den / when does the snow end?\n"
-    "goodbye little dog / you dug some holes in your day / they'll be hard to fill.\n"
-    "when life shuts a door, / just open it. it’s a door. / that is how doors work.\n"
+const char* const FRAME_V08 =
+    "\x28\xB5\x2F\xFD\x24\xEF\x35\x05\x00\x92\x0B\x21\x1F\xB0\x01\x10"
+    "\x00\x00\x00\x35\x59\xA6\xE7\xA1\xEF\x7C\xFC\xBD\x3F\xFF\x9F\xEF"
+    "\xEE\xEF\x61\xC3\xAA\x31\x1D\x34\x38\x22\x22\x04\x44\x21\x80\x32"
+    "\xAD\x28\xF3\xD6\x28\x0C\x0A\x0E\xD6\x5C\xAC\x19\x8D\x20\x5F\x45"
+    "\x02\x2E\x17\x50\x66\x6D\xAC\x8B\x9C\x6E\x07\x73\x46\xBB\x44\x14"
+    "\xE7\x98\xC3\xB9\x17\x32\x6E\x33\x7C\x0E\x21\xB1\xDB\xCB\x89\x51"
+    "\x23\x34\xAB\x9D\xBC\x6D\x20\xF5\x03\xA9\x91\x4C\x2E\x1F\x59\xDB"
+    "\xD9\x35\x67\x4B\x0C\x95\x79\x10\x00\x85\xA6\x96\x95\x2E\xDF\x78"
+    "\x7B\x4A\x5C\x09\x76\x97\xD1\x5C\x96\x12\x75\x35\xA3\x55\x4A\xD4"
+    "\x0B\x00\x35\x0B\x71\xB5\xC0\x2A\x5C\xE6\x08\x45\xF1\x39\x43\xF1"
+    "\x1C\x4B\x54\x10\x9D\x31\x50\x85\x4B\x54\x0E\x01\x4B\x3D\x01\xD2"
+    "\x2F\x21\x80";
 
-    "snowden is snowed in / he's now then in his snow den / when does the snow end?\n"
-    "goodbye little dog / you dug some holes in your day / they'll be hard to fill.\n"
-    "when life shuts a door, / just open it. it’s a door. / that is how doors work.\n"
 
+const char* const BLOCK =
     "snowden is snowed in / he's now then in his snow den / when does the snow end?\n"
     "goodbye little dog / you dug some holes in your day / they'll be hard to fill.\n"
     "when life shuts a door, / just open it. it’s a door. / that is how doors work.\n";
diff --git a/tests/test-variants.sh b/tests/test-variants.sh
index f3a9e065bde..36803e8ff8a 100755
--- a/tests/test-variants.sh
+++ b/tests/test-variants.sh
@@ -97,10 +97,8 @@ cliextra_not_present "$ZSTD_DICTBUILDER"
 legacy_not_present "$ZSTD_DICTBUILDER"
 legacy_not_present "$ZSTD_NOLEGACY"
 
-symbol_not_present "$ZSTD" ZSTDv01
-symbol_not_present "$ZSTD" ZSTDv02
-symbol_not_present "$ZSTD" ZSTDv03
-symbol_not_present "$ZSTD" ZSTDv04
+# since v1.6.0, the default CLI is built without any legacy decoder
+legacy_not_present "$ZSTD"
 
 test_compress "$ZSTD_COMPRESS"
 test_decompress "$ZSTD_DECOMPRESS"