Linux supports the stdcall calling convention, either via functions
explicitly declared with the stdcall attribute, or via code compiled
with -mrtd which effectively makes stdcall the default.
This introduces FFI_STDCALL, FFI_THISCALL, and FFI_FASTCALL on
non-Windows x86-32 platforms, as non-default calling conventions.
ffi_prep_cif_core had a special case for X86_WIN32, checking for
FFI_THISCALL in addition to the FFI_FIRST_ABI-to-FFI_LAST_ABI range
before returning FFI_BAD_ABI. However, on X86_WIN32, FFI_THISCALL
already falls in that range, making the special case unnecessary.
Remove it.
testsuite/libffi.call/closure_stdcall.c and
testsuite/libffi.call/closure_thiscall.c include inline assembly to save
the stack pointer before and after the call, and compare the values.
However, compilers can and do leave the stack in different states for
these two pieces of inline assembly, such as by saving a temporary value
on the stack across the call; observed with gcc -Os, and verified as
spurious through careful inspection of disassembly.
The test case testsuite/libffi.call/many_win32.c can spuriously fail due
to excess floating-point precision. Instrumenting it with some printf
calls shows differences well above FLT_EPSILON. (Note when
instrumenting it that multiple computations of the difference, such as
one in a print and another in the conditional, may produce different
results.)
Rather than complicating the test suite with architecture-specific flags
to avoid excess precision, just simplify the floating-point computation
to avoid a dependency on potential excess precision.
The test case testsuite/libffi.call/many.c can spuriously fail due to
excess floating-point precision. Instrumenting it with some printf
calls shows differences well above FLT_EPSILON. (Note when
instrumenting it that multiple computations of the difference, such as
one in a print and another in the conditional, may produce different
results.)
Rather than complicating the test suite with architecture-specific flags
to avoid excess precision, just simplify the floating-point computation
to avoid a dependency on potential excess precision.
src/x86/ffi64.c: In function 'classify_argument':
src/x86/ffi64.c:205:5: error: duplicate case value
case FFI_TYPE_LONGDOUBLE:
^
src/x86/ffi64.c:202:5: error: previously used here
case FFI_TYPE_DOUBLE:
^
Anthony Green
Josh Triplett
Ryan VanderMeulen
Heiher