diff --git a/HISTORY.rst b/HISTORY.rst
index 6685876e..05fa7288 100644
--- a/HISTORY.rst
+++ b/HISTORY.rst
@@ -18,6 +18,7 @@ PlatformIO Core 6
 
 * Control |UNITTESTING| verbosity with a new multilevel `pio test -v <https://docs.platformio.org/en/latest/core/userguide/cmd_test.html#cmdoption-pio-test-v>`__ command option (`issue #4276 <https://github.com/platformio/platformio-core/issues/4276>`_)
 * Fixed an issue when the `build_src_flags <https://docs.platformio.org/en/latest/projectconf/section_env_build.html#build-src-flags>`__ option was applied outside the project scope (`issue #4277 <https://github.com/platformio/platformio-core/issues/4277>`_)
+* Fixed an issue with debugging assembly files without preprocessor (".s")
 
 6.0.1 (2022-05-17)
 ~~~~~~~~~~~~~~~~~~
diff --git a/docs b/docs
index 5c3659ac..17a3f640 160000
--- a/docs
+++ b/docs
@@ -1 +1 @@
-Subproject commit 5c3659ac2fb3bd27e54ca0fe3d151c7a200158d8
+Subproject commit 17a3f640ac409056db131f2093dd7319fca9157c
diff --git a/platformio/builder/tools/piomisc.py b/platformio/builder/tools/piomisc.py
index 75fec40a..76ec2e37 100644
--- a/platformio/builder/tools/piomisc.py
+++ b/platformio/builder/tools/piomisc.py
@@ -114,7 +114,15 @@ def ConfigureDebugTarget(env):
     ]
 
     if optimization_flags:
-        env.AppendUnique(ASFLAGS=optimization_flags, LINKFLAGS=optimization_flags)
+        env.AppendUnique(
+            ASFLAGS=[
+                # skip -O flags for assembler
+                f
+                for f in optimization_flags
+                if f.startswith("-g")
+            ],
+            LINKFLAGS=optimization_flags,
+        )
 
 
 def GetExtraScripts(env, scope):