Command to build _testexternalinspection.o gets truncated when building under WASI

[brettcannon]

Bug description:

The output from make is:

z stack-size=524288 -Wl,--stack-first -Wl,--initial-memory=10485760   Modules/_testexternalinspection.o   -o Modules/_testexternalinspection.cpython-313d-wasm32-wasi.so
/bin/sh: 1: z: not found

It seems like the command is partially from CONFIGURE_LDFLAGS_NODIST= -z stack-size=524288 -Wl,--stack-first -Wl,--initial-memory=10485760.

And the Makefile line is:

Modules/_testexternalinspection$(EXT_SUFFIX):  Modules/_testexternalinspection.o; $(BLDSHARED)  Modules/_testexternalinspection.o $(MODULE__TESTEXTERNALINSPECTION_LDFLAGS) $(MODULE_LDFLAGS) -o Modules/_testexternalinspection$(EXT_SUFFIX)

But BLDSHARED is BLDSHARED= $(PY_CORE_LDFLAGS) in Makefile. That suggests there's some expansion failing.

CPython versions tested on:

CPython main branch

Operating systems tested on:

Other

[erlend-aasland]

cc. @mhsmith

[mhsmith]

I'm not sure what's going on here, but I don't think it's caused by any of the things I've changed recently.

[erlend-aasland]

@brettcannon, how can I reproduce? I tried following the instructions in Tools/wasm/README.md but got no build failure.

[brettcannon]

@brettcannon, how can I reproduce? I tried following the instructions in Tools/wasm/README.md but got no build failure.

@erlend-aasland the overall build will succeed, but _testexternalinspection won't be kept due to not being imported. I only noticed this because I had another build failure related to that module that I have fixed.

[mhsmith]

If I understand correctly, WASI doesn't actually support building shared library modules at all, so it doesn't set BLDSHARED. But _testexternalinspection was added to a small list of test modules at the bottom of Setup.stdlib.in which "MUST be built as shared libraries". The reason this has never caused a problem for WASI before is that all the other modules in the list are skipped due to WASI not supporting dlopen.

[brettcannon]

@mhsmith Correct, but all the other modules fail due to not being importable (I have #115983 to track turning off building them in the first place). For some reason with _testkexternalinspection I see this odd situation where the command run gets truncated down to z and causes the compilation to fail.

[brettcannon]

The list of modules that @mhsmith referred to:

cpython/Modules/Setup.stdlib.in

Lines 170 to 180 in c951e25

	# Some testing modules MUST be built as shared libraries.
	*shared*
	@MODULE__TESTIMPORTMULTIPLE_TRUE@_testimportmultiple _testimportmultiple.c
	@MODULE__TESTMULTIPHASE_TRUE@_testmultiphase _testmultiphase.c
	@MODULE__TESTSINGLEPHASE_TRUE@_testsinglephase _testsinglephase.c
	@MODULE__TESTEXTERNALINSPECTION_TRUE@_testexternalinspection _testexternalinspection.c
	@MODULE__CTYPES_TEST_TRUE@_ctypes_test _ctypes/_ctypes_test.c
	# Limited API template modules; must be built as shared modules.
	@MODULE_XXLIMITED_TRUE@xxlimited xxlimited.c
	@MODULE_XXLIMITED_35_TRUE@xxlimited_35 xxlimited_35.c

If we don't want to bother trying to figure out why the truncation is occurring I can just turn off trying to build this module under WASI (and all the other ones listed there).

[sobolevn]

I just tried the whole thing on my mac, I got expected result: BLDSHARED= $(CC) -bundle -undefined dynamic_lookup $(PY_CORE_LDFLAGS)

No warning happened when running make.

[mhsmith]

@sobolevn: From that command line, it looks like you were building for macOS, not WASI.

[brettcannon]

I turned off building _testexternalinspection under WASI in #116528 . I'm going to close this as indirectly fixed, but if someone wanted to continue to dig into why the command is getting truncated I can open it again.