Skip ftruncate_bug76422 if disk_free_space() <= 4GB

[TysonAndre]

Followup to #5043

In the middle of running this test with TESTS=-j9,
run-tests.php stopped the test suite because the partition started
with 3.5GB of free disk space and new test files couldn't be created.

Reclaiming the disk space of that file also took a while.

[cmb69]

LGTM. Thanks!

[TysonAndre]

The build failure in php-src for Mac is unrelated, it's related to compiling the recent changes in the opcache jit

/bin/bash --noprofile --norc /Users/runner/runners/2.165.2/work/_temp/ebce46e0-54f7-49f1-acf8-8ca6de005353.sh
mkdir: ext/intl/grapheme/.libs: File exists
In file included from /Users/runner/runners/2.165.2/work/1/s/ext/opcache/jit/zend_jit.c:3242:
ext/opcache/jit/zend_jit_trace.c:1668:2: error: shifting a negative signed value is undefined [-Werror,-Wshift-negative-value]
        TRACE_FRAME_INIT(frame, op_array, 0, -1);
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ext/opcache/jit/zend_jit_internal.h:355:49: note: expanded from macro 'TRACE_FRAME_INIT'
                _frame->_info = (uint32_t)((((int)(num_args)) << TRACE_FRAME_SHIFT_NUM_ARGS) & TRACE_FRAME_MASK_NUM_ARGS); \
                                            ~~~~~~~~~~~~~~~~~ ^
In file included from /Users/runner/runners/2.165.2/work/1/s/ext/opcache/jit/zend_jit.c:3242:
ext/opcache/jit/zend_jit_trace.c:2894:5: error: shifting a negative signed value is undefined [-Werror,-Wshift-negative-value]
                                TRACE_FRAME_INIT(call, op_array, 0, -1); // TODO: should be possible to get the real number af arguments ???
                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ext/opcache/jit/zend_jit_internal.h:355:49: note: expanded from macro 'TRACE_FRAME_INIT'
                _frame->_info = (uint32_t)((((int)(num_args)) << TRACE_FRAME_SHIFT_NUM_ARGS) & TRACE_FRAME_MASK_NUM_ARGS); \
                                            ~~~~~~~~~~~~~~~~~ ^
In file included from /Users/runner/runners/2.165.2/work/1/s/ext/opcache/jit/zend_jit.c:3242:
ext/opcache/jit/zend_jit_trace.c:2940:5: error: shifting a negative signed value is undefined [-Werror,-Wshift-negative-value]
                                TRACE_FRAME_INIT(frame, op_array, 0, -1);
                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ext/opcache/jit/zend_jit_internal.h:355:49: note: expanded from macro 'TRACE_FRAME_INIT'
                _frame->_info = (uint32_t)((((int)(num_args)) << TRACE_FRAME_SHIFT_NUM_ARGS) & TRACE_FRAME_MASK_NUM_ARGS); \
                                            ~~~~~~~~~~~~~~~~~ ^
3 errors generated.
make: *** [ext/opcache/jit/zend_jit.lo] Error 1
make: *** Waiting for unfinished jobs....

[divinity76]

were you running this test on FAT32? i can see this being a problem on filesystems that does not support sparse files, but i thought all modern filesystems (even the Apple/MacOS ones) supported sparse files?

[divinity76]

oh, apparently Apple's FS supports sparse files, but only since 2017, so if you have a 2016 MacOS/iOS system, you don't have sparse file support.. guess that's what's happened here?

(by comparison, Linux has supported sparse files since at least 1993 with the introduction of ext2)

[TysonAndre]

i can see this being a problem on filesystems that does not support sparse files, but i thought all modern filesystems (even the Apple/MacOS ones) supported sparse files?

@divinity76 the tests were run on an ecryptfs filesystem, which is a filesystem which apparently doesn't efficiently support ftruncate - https://askubuntu.com/questions/100752/how-does-ecryptfs-impact-harddisk-performance