Implement support for breaking into debugger under Linux #585
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Use Linux-specific /proc/$PID/status file to check whether we're being debugged and a generic raise(SIGTRAP) to actually break into the debugger.
Don't duplicate Catch::isDebuggerActive() check many times, do it just once in CATCH_BREAK_INTO_DEBUGGER() definition and use a separate CATCH_TRAP() macro for the really platform-dependent part.
This is more convenient than using the generic portable raise(SIGTRAP) as it avoids having another stack frame in the debugger when the break happens.
| // directly at the location of the failing check instead of breaking inside | ||
| // raise() called from it, i.e. one stack frame below. | ||
| #if defined(__GNUC__) && (defined(__i386) || defined(__x86_64)) | ||
| #define CATCH_TRAP() asm volatile ("int $3") |
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How about using __builtin_trap() available on both gcc and clang to avoid the architecture dependence ? Though it will not specifically raise SIGTRAP.
EDIT: On gcc 5.3.0 and clang 3.7.1, it raises SIGILL. It is kind of confusing to see "Illegal instruction" for an expected break. Thus I think your solution is better. 👍
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Any reason this isn't merged yet? |
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Since there is interest in this functionality (#372 is very similar), Ill try to take a look soon. |
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This PR seems to bring in about 13% runtime penalty for failing tests, even if Since masses of failing tests are not the usual use case, this probably is not a problem, but it seems to suggest that there is something wrong with how the debugger check is gated if |
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This is really strange, I admit I haven't tested the performance implications of this, but I just don't see how could it affect the execution time so much without FWIW with Thanks for looking at this! |
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I've made branch for performance improvements, Anyway, the penalty isn't that bad, but it could bear looking into later. |
This makes
-bcommand line option to work under Linux.Only tested under amd64, but should work on any architectures, in theory.