GDB 7.10 from NDK r11b returns inconsistent MI result record for -exec-step command

[dosvidos]

I'm debugging UE4 demo with GDB 7.10 from NDK R11B for Windows 64-bit connected to AARCH64 API23 target.
Sometimes, GDB responds with seemingly incorrect async MI result record after the target's execution is resumed by -exec-step command.
According to GDB MI documentation and GDB test suite I expect that in this case the MI result record should always contain a reason field: *stopped,reason="end-stepping-range"
This is also baked by changelog note
2009-02-14 Vladimir Prus [email protected]
* lib/mi-support.exp (mi_expect_stop): Adjust the order of fields.
(mi_expect_interrupt): Likewise.
* gdb.mi/mi-cli.exp: Check that "step" results in proper *stopped
response.
and test cases defined in
binutils-gdb/gdb/testsuite/gdb.mi/mi-cli.exp
This stop without a reason behavior is irritating, because it doesn't fit into expected response pattern. Should the front-end treat a step request as successfully completed after receiving this notification record? This inconsistency requires additional and unnecessary decision-making logic on the front-end.

2016-03-31 17:45:27.7085[GDB] cmd: "46-exec-step --thread 10"
2016-03-31 17:45:27.7390[GDB] stdout: 46^running
2016-03-31 17:45:27.7390[GDB] stdout: *running,thread-id="all"
2016-03-31 17:45:27.9372[GDB] stdout: *stopped,reason="end-stepping-range",frame={addr="0x5247895c",func="FString::FString",args=[{name="this",value="0x597ed088"},{name="Src",value="0x592cc53d "/UE4Game/""},{name="Dummy",value="0x0"}],file="Runtime/Core/Public\Containers/UnrealString.h",fullname="C:\UnrealEngine-4.10\Engine\Source\Runtime\Core\Public\Containers\UnrealString.h",line="124"},thread-id="10",stopped-threads="all",core="1"

2016-03-31 17:45:34.8915[GDB] cmd: "67-exec-finish --thread 10 --frame 0"
2016-03-31 17:45:34.9205[GDB] stdout: 67^running
2016-03-31 17:45:34.9205[GDB] stdout: *running,thread-id="all"
2016-03-31 17:45:36.5448[GDB] stdout: *stopped,reason="end-stepping-range",frame={addr="0x52478a40",func="InitCommandLine",args=[],file="C:\UnrealEngine-4.10\Engine\Source\Runtime\Launch\Private\Android/LaunchAndroid.cpp",fullname="C:\UnrealEngine-4.10\Engine\Source\Runtime\Launch\Private\Android\LaunchAndroid.cpp",line="168"},thread-id="10",stopped-threads="all",core="1"

2016-03-31 17:45:38.9636[GDB] cmd: "89-exec-step --thread 10"
2016-03-31 17:45:38.9936[GDB] stdout: *running,thread-id="all"
2016-03-31 17:45:38.9936[GDB] stdout: 89^running
2016-03-31 17:45:39.1102[GDB] stdout: *stopped,reason="end-stepping-range",frame={addr="0x52478a4c",func="operator+(FString const&, FString&&)",args=[{name="Lhs",value="..."},{name="Rhs",value="<unknown type in C:\UnrealEngine-4.10\NVIDIA_Android_Lab_GDC2016\Binaries\Android\libUE4.so, CU 0x0, DIE 0x2155ba>"}],file="Runtime/Core/Public\Containers/UnrealString.h",fullname="C:\UnrealEngine-4.10\Engine\Source\Runtime\Core\Public\Containers\UnrealString.h",line="679"},thread-id="10",stopped-threads="all",core="1"

2016-03-31 17:45:41.0039[GDB] cmd: "106-exec-finish --thread 10 --frame 0"
2016-03-31 17:45:41.0322[GDB] stdout: 106^running
2016-03-31 17:45:41.0322[GDB] stdout: *running,thread-id="all"
2016-03-31 17:45:47.2672[GDB] stdout: *stopped,reason="end-stepping-range",frame={addr="0x524791f4",func="InitCommandLine",args=[],file="C:\UnrealEngine-4.10\Engine\Source\Runtime\Launch\Private\Android/LaunchAndroid.cpp",fullname="C:\UnrealEngine-4.10\Engine\Source\Runtime\Launch\Private\Android\LaunchAndroid.cpp",line="168"},thread-id="10",stopped-threads="all",core="1"

2016-03-31 17:45:56.8990[GDB] cmd: "128-exec-step --thread 10"
2016-03-31 17:45:56.9080[GDB] stdout: *running,thread-id="all"
2016-03-31 17:45:56.9080[GDB] stdout: 128^running
2016-03-31 17:45:56.9080[GDB TargetState] targetIsRunning is changed from False to True
2016-03-31 17:45:56.9300[GDB] stdout: ~"FApp::IsGameNameEmpty () at Runtime/Core/Public/Misc/App.h:180\n"
2016-03-31 17:45:56.9300[GDB] stdout: ~"180\t\t\treturn (GInternalGameName[0] == 0);\n"
2016-03-31 17:45:56.9300[GDB] stdout: *stopped,frame={addr="0x524791f4",func="FApp::IsGameNameEmpty",args=[],file="Runtime/Core/Public/Misc/App.h",fullname="C:\UnrealEngine-4.10\Engine\Source\Runtime\Core\Public\Misc\App.h",line="180"},thread-id="10",stopped-threads="all",core="1"

[dosvidos]

The func="FApp::IsGameNameEmpty" is defined in a header file and decorated with
#define FORCEINLINE inline __attribute__ ((always_inline)) /* Force code to be inline */ FORCEINLINE static bool IsGameNameEmpty() { return (GInternalGameName[0] == 0); }
But the same attribute is applied to func="FString::FString" and func="operator+(FString const&, FString&&)" and yet for both of them GDB outputs the expected response *stopped,reason="end-stepping-range"

[jmgao]

Try gdb 7.11 from the r12 beta, we've had internal reports of single stepping being broken with 7.10 that were resolved with 7.11.

[DanAlbert]

Is this fixed?

[DanAlbert]

Re-open if this is still present in r12.