cpu-exec: Fix compiler warning (-Werror=clobbered)

Reloading of local variables after sigsetjmp is only needed for some
buggy compilers.

The code which should reload these variables causes compiler warnings
with gcc 4.7 when compiler optimizations are enabled:

cpu-exec.c:204:15: error:
 variable ‘cpu’ might be clobbered by ‘longjmp’ or ‘vfork’ [-Werror=clobbered]
cpu-exec.c:207:15: error:
 variable ‘cc’ might be clobbered by ‘longjmp’ or ‘vfork’ [-Werror=clobbered]
cpu-exec.c:202:28: error:
 argument ‘env’ might be clobbered by ‘longjmp’ or ‘vfork’ [-Werror=clobbered]

Now this code is only used for compilers which need it
(and gcc 4.5.x, x > 0 which does not need it but won't give warnings).

There were bug reports for clang and gcc 4.5.0, while gcc 4.5.1
was reported to work fine without the reload code. For clang it
is not clear which versions are affected, so simply keep the status quo
for all clang compilations. This can be improved later.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Message-Id: <1443266606-21400-1-git-send-email-sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
1 file changed
tree: 2d8f71f198893a41c26018e0cdc509ab023d76b4
  1. audio/
  2. backends/
  3. block/
  4. bsd-user/
  5. contrib/
  6. crypto/
  7. default-configs/
  8. disas/
  9. docs/
  10. fpu/
  11. fsdev/
  12. gdb-xml/
  13. hw/
  14. include/
  15. libdecnumber/
  16. linux-headers/
  17. linux-user/
  18. migration/
  19. net/
  20. pc-bios/
  21. po/
  22. qapi/
  23. qga/
  24. qobject/
  25. qom/
  26. roms/
  27. scripts/
  28. slirp/
  29. stubs/
  30. target-alpha/
  31. target-arm/
  32. target-cris/
  33. target-i386/
  34. target-lm32/
  35. target-m68k/
  36. target-microblaze/
  37. target-mips/
  38. target-moxie/
  39. target-openrisc/
  40. target-ppc/
  41. target-s390x/
  42. target-sh4/
  43. target-sparc/
  44. target-tilegx/
  45. target-tricore/
  46. target-unicore32/
  47. target-xtensa/
  48. tcg/
  49. tests/
  50. trace/
  51. ui/
  52. util/
  53. .dir-locals.el
  54. .exrc
  55. .gitignore
  56. .gitmodules
  57. .mailmap
  58. .travis.yml
  59. accel.c
  60. aio-posix.c
  61. aio-win32.c
  62. arch_init.c
  63. async.c
  64. balloon.c
  65. block.c
  66. blockdev-nbd.c
  67. blockdev.c
  68. blockjob.c
  69. bootdevice.c
  70. bt-host.c
  71. bt-vhci.c
  72. Changelog
  73. CODING_STYLE
  74. configure
  75. COPYING
  76. COPYING.LIB
  77. cpu-exec-common.c
  78. cpu-exec.c
  79. cpus.c
  80. cputlb.c
  81. device-hotplug.c
  82. device_tree.c
  83. disas.c
  84. dma-helpers.c
  85. dump.c
  86. exec.c
  87. gdbstub.c
  88. HACKING
  89. hmp-commands-info.hx
  90. hmp-commands.hx
  91. hmp.c
  92. hmp.h
  93. iohandler.c
  94. ioport.c
  95. iothread.c
  96. kvm-all.c
  97. kvm-stub.c
  98. LICENSE
  99. main-loop.c
  100. MAINTAINERS
  101. Makefile
  102. Makefile.objs
  103. Makefile.target
  104. memory.c
  105. memory_mapping.c
  106. module-common.c
  107. monitor.c
  108. nbd.c
  109. numa.c
  110. os-posix.c
  111. os-win32.c
  112. page_cache.c
  113. qapi-schema.json
  114. qdev-monitor.c
  115. qdict-test-data.txt
  116. qemu-bridge-helper.c
  117. qemu-char.c
  118. qemu-doc.texi
  119. qemu-ga.texi
  120. qemu-img-cmds.hx
  121. qemu-img.c
  122. qemu-img.texi
  123. qemu-io-cmds.c
  124. qemu-io.c
  125. qemu-log.c
  126. qemu-nbd.c
  127. qemu-nbd.texi
  128. qemu-options-wrapper.h
  129. qemu-options.h
  130. qemu-options.hx
  131. qemu-seccomp.c
  132. qemu-tech.texi
  133. qemu-timer.c
  134. qemu.nsi
  135. qemu.sasl
  136. qjson.c
  137. qmp-commands.hx
  138. qmp.c
  139. qtest.c
  140. README
  141. rules.mak
  142. softmmu_template.h
  143. spice-qemu-char.c
  144. tcg-runtime.c
  145. tci.c
  146. thread-pool.c
  147. thunk.c
  148. tpm.c
  149. trace-events
  150. translate-all.c
  151. translate-all.h
  152. translate-common.c
  153. user-exec.c
  154. VERSION
  155. version.rc
  156. vl.c
  157. xen-common-stub.c
  158. xen-common.c
  159. xen-hvm-stub.c
  160. xen-hvm.c
  161. xen-mapcache.c