Description Lars M. 2015-02-23 08:31:33 EST

MinGW GDB dies with at SIGINT

I encounter a reproducible failure of GDB when using MinGW or MinGW-w64 on Windows.

Affects:

* eclipse-cpp-luna-SR1a-win32-x86_64
* stable release: mingw64-x64-4.8.1-release-posix-seh-rev5
* most recent release: mingw64-x86_64-4.9.2-release-posix-seh-rt_v3-rev1
* MinGW from https://sourceforge.net/projects/mingw

C:\mingw32\bin>gcc -v
Using built-in specs.
COLLECT_GCC=gcc
Target: mingw32
Configured with: ../gcc-4.6.2/configure --enable-languages=c,c++,ada,fortran,objc,obj-c++ --disable-sjlj-exceptions --with-dwarf2 --enable-shared --enable-libgomp --disable-win32-registry --enable-libstdcxx-debug --enable-version-specific-runtime-libs --build=mingw32 --prefix=/mingw
Thread model: win32
gcc version 4.6.2 (GCC)

C:\mingw32\bin>gdb -v
GNU gdb (GDB) 7.4

* Windows 7 64bit

Please note, that there are no issues with this code on Linux.



Test code:

[code]
int main(int argc, char **argv)
{
    string line;
    getline(cin, line);
    printf("your line: %s\n", line.c_str());
    return 0;
}
[/code]



Steps to reproduce:

* Build the code with one of the Toolchains mentioned above (using -std=c++0x)
* Launch the program in debug mode.
* Let it run till getline() is called
* Insert a breakpoint at the printf() line



Actual Result:

The program does not respond to user input, GDB does not respond to interrupt or any other commands. An error is thrown: "Breakpoint installation failed: Breakpoint insertion failure"

Significant lines of GDB output:

[code]
132,543 31-exec-continue --thread 1
132,547 31^running
132,547 *running,thread-id="all"
132,547 (gdb)
134,596 =thread-created,id="2",group-id="i1"
134,598 ~"[New Thread 3880.0x1258]\n"
134,598 *running,thread-id="all"
134,602 ~"\nProgram received signal "
134,602 ~"SIGINT, Interrupt.\n"
134,603 ~"[Switching to Thread 3880.0x1258]\n"
134,605 ~"0x0000000076ca49f2 in KERNEL32!CtrlRoutine () from C:\\Windows\\system32\\kernel32.dll\n"
134,605 *stopped,reason="signal-received",signal-name="SIGINT",signal-meaning="Interrupt",frame={add\
r="0x0000000076ca49f2",func="KERNEL32!CtrlRoutine",args=[],from="C:\\Windows\\system32\\kernel32.dll\
"},thread-id="2",stopped-threads="all"
134,607 =thread-selected,id="2"
134,607 (gdb)
134,607 32-break-insert -f D:\\app\\main.cpp:147
[/code]



Expected Result:

Successfully tested with GDB on CMD:

* Open CMD and change to directory containing the executable
* Start executable and look-up its process number (<PID>)
* Open another CMD and start GDB
* In GDB execute the following commands
[code]
attach <PID>
break D:\\app\\main.cpp:147
continue
[/code]
* Switch to first CMD and enter a line and hit <Enter> key
* Switch back to GDB, you should see sth. like:
[code]
Breakpoint 1, main (argc=1, argv=0x4dfe20)
    at D:\10216_wimbus\sources\serial-interface\app\main.cpp:147
147             printf("your line: %s\n", line.c_str());
[/code]
* Now you can step through the rest of the program by entering step



References:

I selected the Toolchain following the (https://qt-project.org/wiki/MinGW-64-bit) Qt Project recommondations.

I found a mailing list thread that may be related to this issue: (https://eclipse.1072660.n5.nabble.com/target-unexpectedly-stops-on-a-SIGINT-while-setting-breakpoint-on-running-target-td62921.html) target unexpectedly stops on a SIGINT while setting breakpoint on running target.

There is a bug report related to this mailing list thread: (https://bugs.eclipse.org/bugs/show_bug.cgi?id=304721) Bug 304721 - Use GDB async mode for GDB 7.0
I'm not sure if this bug is related.


I posted about this issue in the eclipse forums and asked for confirmation, but after 3 days and no reply I decided to report this as a bug.

Currently to me it looks like developing Windows applications on Windows using MinGW and Eclipse CDT is impossible.

Please tell me if I am doing something wrong.