Unbreak fiber for ELF PowerPC building with Clang

[brad0]

Clang also defines the uppercase __POWERPC__ symbol so the commit 2bd8eb02f81ab8297aa89b8cb29b0f3867b9fafe breaks the build on ELF PowerPC systems. Since we know this is already a PowerPC system with BOOST_ARCH_PPC then check for the vendor __APPLE__ instead.

[brad0]

cc @barracuda156

[barracuda156]

@brad0 Thank you, this is something new to hear. Which OS and which clang? Just so that I know.

[brad0]

@brad0 Thank you, this is something new to hear. Which OS and which clang? Just so that I know.

OpenBSD, but this would affect any ELF OS. e.g. *BSD, Linux if building with Clang.

[barracuda156]

Good to know. Should be careful then to always check for __APPLE__ && __POWERPC__. Or at least exclude Clang (__POWERPC__ is also defined on BeOS, AFAIR, but this is not relevant to the present case).

[brad0]

Good to know. Should be careful then to always check for __APPLE__ && __POWERPC__. Or at least exclude Clang (__POWERPC__ is also defined on BeOS, AFAIR, but this is not relevant to the present case).

symbols defined for Clang PowerPC targets..

  // Target identification.
  Builder.defineMacro("__ppc__");
  Builder.defineMacro("__PPC__");
  Builder.defineMacro("_ARCH_PPC");
  Builder.defineMacro("__powerpc__");
  Builder.defineMacro("__POWERPC__");
  if (PointerWidth == 64) {
    Builder.defineMacro("_ARCH_PPC64");
    Builder.defineMacro("__powerpc64__");
    Builder.defineMacro("__PPC64__");
  }

[barracuda156]

Good to know. Should be careful then to always check for __APPLE__ && __POWERPC__. Or at least exclude Clang (__POWERPC__ is also defined on BeOS, AFAIR, but this is not relevant to the present case).

symbols defined for Clang PowerPC targets..

  // Target identification.

  Builder.defineMacro("__ppc__");

  Builder.defineMacro("__PPC__");

  Builder.defineMacro("_ARCH_PPC");

  Builder.defineMacro("__powerpc__");

  Builder.defineMacro("__POWERPC__");

  if (PointerWidth == 64) {

    Builder.defineMacro("_ARCH_PPC64");

    Builder.defineMacro("__powerpc64__");

    Builder.defineMacro("__PPC64__");

  }

(On a side note, what a mess: why would it define __ppc__ for 32- and 64-bit both?)

For BeOS, it does use __POWERPC__, but I am not sure about its assembler syntax. It may be using unprefixed registers in fact, judging from https://opensource.apple.com/source/gcc3/gcc3-1175/gcc/config/rs6000/beos.h.auto.html If so, your change may fix BeOS too.

[brad0]

(On a side note, what a mess: why would it define __ppc__ for 32- and 64-bit both?)

Same goes for __powerpc__ for both.

For BeOS, it does use __POWERPC__, but I am not sure about its assembler syntax. It may be using unprefixed registers in fact, judging from https://opensource.apple.com/source/gcc3/gcc3-1175/gcc/config/rs6000/beos.h.auto.html If so, your change may fix BeOS too.

Even if it had to go the other way you could check add a check for BeOS.

[olk]

ty