diff --git a/esphome/__main__.py b/esphome/__main__.py
index c1e05d2ea7..90737fce4b 100644
--- a/esphome/__main__.py
+++ b/esphome/__main__.py
@@ -855,7 +855,11 @@ def compile_program(args: ArgsProtocol, config: ConfigType) -> int:
         toolchain.create_factory_bin()
         toolchain.create_ota_bin()
         toolchain.create_elf_copy()
-        toolchain.get_idedata()
+        try:
+            toolchain.get_idedata()
+        except EsphomeError as err:
+            # The firmware already built; idedata is a bonus artifact here
+            _LOGGER.warning("Could not generate idedata: %s", err)
     else:
         from esphome.platformio import toolchain
 
diff --git a/esphome/build_helpers/idedata.py b/esphome/build_helpers/idedata.py
index e0b1a8efe4..31b62df528 100644
--- a/esphome/build_helpers/idedata.py
+++ b/esphome/build_helpers/idedata.py
@@ -297,17 +297,8 @@ def idedata_from_build(compile_commands: Path, launcher: str | None = None) -> d
     """
     entries = json.loads(Path(compile_commands).read_text(encoding="utf-8"))
 
-    # ninja-generated compile DBs repeat one identical multi-KB command per
-    # source file; parse each distinct (directory, command) once.
-    parsed: dict[tuple[str, str], tuple[str, list[str], list[str], list[str]]] = {}
-
-    def _parse(entry: dict) -> tuple[str, list[str], list[str], list[str]]:
-        key = (entry["directory"], entry["command"])
-        if key not in parsed:
-            parsed[key] = parse_entry(entry, launcher)
-        return parsed[key]
-
-    cxx_path, defines, _, cxx_flags = _parse(_pick_entry(entries))
+    representative = _pick_entry(entries)
+    cxx_path, defines, rep_includes, cxx_flags = parse_entry(representative, launcher)
     if _is_launcher(cxx_path):
         # Checked before the toolchain probe (which would fail opaquely on
         # a launcher) so the unusable compile DB is named, and never
@@ -317,11 +308,16 @@ def idedata_from_build(compile_commands: Path, launcher: str | None = None) -> d
             "compiler; the compile database is unusable"
         )
 
-    build_includes: dict[str, None] = {}
+    # Seed with the representative's includes so it is not parsed twice
+    # (per-file -c/-o arguments make every command distinct, so memoizing
+    # whole commands would never hit)
+    build_includes: dict[str, None] = dict.fromkeys(
+        rep_includes if _is_esphome_src(representative["file"]) else ()
+    )
     for entry in entries:
-        if not _is_esphome_src(entry["file"]):
+        if entry is representative or not _is_esphome_src(entry["file"]):
             continue
-        for inc in _parse(entry)[2]:
+        for inc in parse_entry(entry, launcher)[2]:
             build_includes.setdefault(inc, None)
 
     return {
diff --git a/tests/unit_tests/test_main.py b/tests/unit_tests/test_main.py
index a40341e194..f81da9052b 100644
--- a/tests/unit_tests/test_main.py
+++ b/tests/unit_tests/test_main.py
@@ -7130,3 +7130,35 @@ def test_warn_source_tree_mismatch_falls_back_when_stat_fails(
 
     # Same tree, so the path comparison still finds them equal and stays silent
     assert not caplog.text
+
+
+def test_compile_program_espidf_idedata_failure_does_not_fail_build(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """A post-compile idedata error is a warning: the firmware already built."""
+    from esphome.const import (
+        KEY_CORE,
+        KEY_TARGET_FRAMEWORK,
+        KEY_TARGET_PLATFORM,
+        Toolchain,
+    )
+    from esphome.core import CORE, EsphomeError
+
+    CORE.toolchain = Toolchain.ESP_IDF
+    CORE.data[KEY_CORE] = {
+        KEY_TARGET_PLATFORM: "esp32",
+        KEY_TARGET_FRAMEWORK: "esp-idf",
+    }
+    with (
+        patch("esphome.espidf.toolchain.run_compile", return_value=0),
+        patch("esphome.espidf.toolchain.create_factory_bin"),
+        patch("esphome.espidf.toolchain.create_ota_bin"),
+        patch("esphome.espidf.toolchain.create_elf_copy"),
+        patch(
+            "esphome.espidf.toolchain.get_idedata",
+            side_effect=EsphomeError("compile database is unusable"),
+        ),
+        patch("esphome.__main__._check_and_emit_build_info"),
+    ):
+        assert compile_program(MagicMock(), {}) == 0
+    assert "Could not generate idedata" in caplog.text
diff --git a/tests/unit_tests/test_platformio_library.py b/tests/unit_tests/test_platformio_library.py
index 4088cac1f8..0acb0d69cb 100644
--- a/tests/unit_tests/test_platformio_library.py
+++ b/tests/unit_tests/test_platformio_library.py
@@ -564,3 +564,15 @@ def test_split_flag_entry_non_string_is_clean() -> None:
         split_flag_entry({"esp32": ["-DX"]}, "lib x")
     with pytest.raises(EsphomeError, match="Malformed build flag 5"):
         split_flag_entry(5, "lib x")
+
+
+def test_source_kind_map_shape() -> None:
+    """The kind values the native compile rules key on, and the deliberate
+    AS/ASPP merge (.s and .S both map to asm)."""
+    from esphome.platformio.library import SOURCE_KIND_FOR_SUFFIX
+
+    assert set(SOURCE_KIND_FOR_SUFFIX.values()) == {"c", "cxx", "asm"}
+    assert SOURCE_KIND_FOR_SUFFIX[".s"] == "asm"
+    assert SOURCE_KIND_FOR_SUFFIX[".S"] == "asm"
+    assert SOURCE_KIND_FOR_SUFFIX[".c"] == "c"
+    assert SOURCE_KIND_FOR_SUFFIX[".cpp"] == "cxx"