Bug#887494: mozjs52: FTBFS on sparc64: interpreter segfaults

[Simon McVittie <smcv@debian.org>]

Source: mozjs52
Version: 52.3.1-7
Severity: normal

mozjs52 runs a smoke-test on the js sample interpreter (which is no longer
installed, but is still built) to check whether the built binaries are
in any way functional. On sparc64, the answer is that they are not:

>    debian/rules override_dh_auto_test
> make[1]: Entering directory '/<<PKGBUILDDIR>>'
> SRCDIR=/<<PKGBUILDDIR>>/js/src DEB_HOST_ARCH=sparc64 /<<PKGBUILDDIR>>/debian/test.sh
> Segmentation fault
> Smoke-test failed: did interpreter initialization fail? (see #873778)
> debian/rules:99: recipe for target 'override_dh_auto_test' failed

The failing command is:

    "$SRCDIR/js/src/js" -e 'print("Hello, world")'

so this probably indicates that sparc64 builds of mozjs are unable to
interpret JavaScript at all.

This appears to be a regression since mozjs24, which passed at least some
of its build-time tests on sparc64. Maybe mozjs52 is making assumptions
about the layout of virtual memory that are not true on sparc64?

If there are patches for sparc64 in firefox-esr or in upstream Firefox,
they are probably also applicable to mozjs52.

Regards,
    smcv