py/mkrules,makeqstrdefs: Fix argument list too long error in qstr generation.

Support response files in makeqstrdefs.py to handle builds with large
numbers of source files (e.g., LVGL with 1200+ files). This prevents
shell argument limit exceeded errors during the qstr preprocessing step.

The issue was first encountered when including large modules like LVGL.
The ARG_MAX limit varies between systems (128KB - 2MB depending on kernel
version), which explains why builds succeed on some machines but fail on
others with identical source code.

Changes:
- Modified py/mkrules.mk to write source file list to qstr_sources.txt
- Modified py/mkrules.cmake to use inline string replacement
- Modified py/makeqstrdefs.py to read from response files with @ prefix

This targeted fix only puts the large file list in a separate file while
keeping all other arguments on the command line.

Signed-off-by: Andrew Leech <[email protected]>

Author: pi-anl

py/makeqstrdefs.py

@@ -198,7 +198,12 @@ class Args:
             if arg in named_args:
                 current_tok = arg
             else:
-                named_args[current_tok].append(arg)
+                # Support response files (starting with @) to avoid argument list too long errors
+                if arg.startswith("@") and os.path.isfile(arg[1:]):
+                    with open(arg[1:], "r") as f:
+                        named_args[current_tok].extend(f.read().splitlines())
+                else:
+                    named_args[current_tok].append(arg)
 
         if not named_args["pp"] or len(named_args["output"]) != 1:
             print("usage: %s %s ..." % (sys.argv[0], " ... ".join(named_args)))

py/mkrules.cmake

@@ -122,9 +122,14 @@ add_custom_target(
 # If any of the dependencies in this rule change then the C-preprocessor step must be run.
 # It only needs to be passed the list of MICROPY_SOURCE_QSTR files that have changed since
 # it was last run, but it looks like it's not possible to specify that with cmake.
+
+# Write source list to response file (convert semicolon-separated to newline-separated)
+string(REPLACE ";" "\n" _qstr_sources_newline "${MICROPY_SOURCE_QSTR}")
+file(WRITE "${MICROPY_GENHDR_DIR}/qstr_sources.txt" "${_qstr_sources_newline}")
+
 add_custom_command(
     OUTPUT ${MICROPY_QSTRDEFS_LAST}
-    COMMAND ${Python3_EXECUTABLE} ${MICROPY_PY_DIR}/makeqstrdefs.py pp ${CMAKE_C_COMPILER} -E output ${MICROPY_GENHDR_DIR}/qstr.i.last cflags ${MICROPY_CPP_FLAGS} -DNO_QSTR cxxflags ${MICROPY_CPP_FLAGS} -DNO_QSTR sources ${MICROPY_SOURCE_QSTR}
+    COMMAND ${Python3_EXECUTABLE} ${MICROPY_PY_DIR}/makeqstrdefs.py pp ${CMAKE_C_COMPILER} -E output ${MICROPY_GENHDR_DIR}/qstr.i.last cflags ${MICROPY_CPP_FLAGS} -DNO_QSTR cxxflags ${MICROPY_CPP_FLAGS} -DNO_QSTR sources @${MICROPY_GENHDR_DIR}/qstr_sources.txt
     DEPENDS ${MICROPY_MPVERSION}
         ${MICROPY_SOURCE_QSTR}
     VERBATIM

py/mkrules.mk

@@ -134,7 +134,9 @@ $(OBJ): | $(HEADER_BUILD)/qstrdefs.generated.h $(HEADER_BUILD)/mpversion.h $(OBJ
 # See more information about this process in docs/develop/qstr.rst.
 $(HEADER_BUILD)/qstr.i.last: $(SRC_QSTR) $(QSTR_GLOBAL_DEPENDENCIES) | $(QSTR_GLOBAL_REQUIREMENTS)
 	$(ECHO) "GEN $@"
-	$(Q)$(PYTHON) $(PY_SRC)/makeqstrdefs.py pp $(CPP) output $(HEADER_BUILD)/qstr.i.last cflags $(QSTR_GEN_CFLAGS) cxxflags $(QSTR_GEN_CXXFLAGS) sources $^ dependencies $(QSTR_GLOBAL_DEPENDENCIES) changed_sources $?
+	$(Q)rm -f $(HEADER_BUILD)/qstr_sources.txt
+	$(Q)for src in $^; do echo "$$src" >> $(HEADER_BUILD)/qstr_sources.txt; done
+	$(Q)$(PYTHON) $(PY_SRC)/makeqstrdefs.py pp $(CPP) output $(HEADER_BUILD)/qstr.i.last cflags $(QSTR_GEN_CFLAGS) cxxflags $(QSTR_GEN_CXXFLAGS) sources @$(HEADER_BUILD)/qstr_sources.txt dependencies $(QSTR_GLOBAL_DEPENDENCIES) changed_sources $?
 
 $(HEADER_BUILD)/qstr.split: $(HEADER_BUILD)/qstr.i.last
 	$(ECHO) "GEN $@"