nacl-gdb 是否仅适用于 *.nexe 而不是 *.pexe 文件?我遵循https://developers.google.com/native-client/devguide/devcycle/debugging#gdb上的指南
./$NACL_SDK_ROOT/toolchain/mac_x86_newlib/bin/x86_64-nacl-gdb
...
This GDB was configured as "--host=i386-apple-darwin10.8.0 --target=x86_64-nacl".
...
(gdb) nacl-manifest code.nmf
(gdb) nacl-irt pnacl/Release/code.pexe
`pnacl/Release/code.pexe': can't read symbols: File format not recognized.