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Diffstat (limited to 'results/scraper/launchpad-without-comments/1030666')
| -rw-r--r-- | results/scraper/launchpad-without-comments/1030666 | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/results/scraper/launchpad-without-comments/1030666 b/results/scraper/launchpad-without-comments/1030666 new file mode 100644 index 000000000..19a872eb6 --- /dev/null +++ b/results/scraper/launchpad-without-comments/1030666 @@ -0,0 +1,30 @@ +gdb can't proceed after a breakpoint + +Using qemu-1.0.1-windows.zip package from http://lassauge.free.fr/qemu/ +Host: Windows 7 Ultimate 64-bit +Guest: i386 system running MS-DOS 6.22 +Launch command line: + qemu-system-i386.exe -L Bios -fda "DOS.vfd" -fdb "Data.vfd" -gdb tcp:127.0.0.1:1234 +Debbugers tried: + gdb 7.3.50.20111026-cvs running on Cygwin 1.7.16 + gdb 7.4 on MinGW + +Short description: +I use gdb to attach to a running Qemu session, set a breakpoint and resume execution. When the breakpoint is hit, gdb gains control as expected. However, trying to single-step or continue at this point just causes the same breakpoint to be hit immediately again. Deleting the breakpoint allows single-stepping or continue to work. + +Steps to reproduce: +DOS.vfd is a floppy image containing an MS-DOS 6.22 startup disk. +Data.vfd is a floppy image containing a single program (hello.com). +The aim is to debug the execution of hello.com with gdb. +Launch Qemu. +Launch gdb, an attach to qemu: + "target remote localhost:1234" +I know the address at which hello.com will be loaded, so set a breakpoint there and resume execution: + "break *0xf730" + "continue" +In Qemu, start hello.com. The breakpoint is immediately hit, execution stops and gdb gains control. +Examining the program gives expected results (such as "info reg" or "disassemble"). +At this point, try to proceed either with single-stepping ("si" or "ni") or with "continue", and the same breakpoint is immediately hit again. Subsequent attempts to single-step or continue just keep hitting the same breakpoint. +The only way to proceed at this point is to delete the breakpoint, after which both single-stepping and continue work. + +Note that single-stepping and continue works as expected if it is done after interrupting execution with Ctrl-C. \ No newline at end of file |