[Interest] Qt 5 Creator 3.3 (Mac) Debugger locks up with endless error logging of "DW_AT_specification(address) has no decl"

[Jim Prouty]

I'm hoping someone can tell me how we can fix our Qt development environment to avoid this frustration:

Way too often Qt Creator 3.3 completely locks up when it hits certain breakpoints in our app using our self-compiled Qt 5.4.1 on Mac OS X 10.9.5.

(It is not clear what causes some breakpoints to lock up when most other breakpoint pose no problem.)

This is a problem we've had with earlier combinations of Qt, Qt Creator and Mac OS X.

When the Qt Creator Debugger UI locks up, stepping or resuming execution are not possible, and the Debugger Log very slowly writes hundreds of errors and warnings about "DW_AT_specification(address) has no decl".

Once this begins, there is no way to recover a working debugging session short of a computer reboot or laborious process-ID genocide.

------- Debugger Log Example Extract ---------
...
warning: (x86_64) /Source/IgorDev7/Igorsrc7/build-IgorPhoenix-64_bit_Qt_5_from_SVN-Debug/debug/IgorWindowUtilities.o 0x2a0009ac67: DW_AT_specification(0x000767fb) has no decl

ERROR: Lldb stderr: warning: (x86_64) /Source/IgorDev7/Igorsrc7/build-IgorPhoenix-64_bit_Qt_5_from_SVN-Debug/debug/wDataClassForEmbeddedQWidget.o 0x2b0009c964: DW_AT_specification(0x0007c91e) has no decl

ERROR: Lldb stderr: warning: (x86_64) /Source/IgorDev7/Igorsrc7/build-IgorPhoenix-64_bit_Qt_5_from_SVN-Debug/debug/CurveFittingDialog.o 0x6c000ba7f1: DW_AT_specification(0x00013bc0) has no decl

ERROR: Lldb stderr: warning: (x86_64) /Source/IgorDev7/Igorsrc7/build-IgorPhoenix-64_bit_Qt_5_from_SVN-Debug/debug/CurveFittingDialog.o 0x6c000ba84f: DW_AT_specification(0x00013c42) has no decl

warning: (x86_64) /Source/IgorDev7/Igorsrc7/build-IgorPhoenix-64_bit_Qt_5_from_SVN-Debug/debug/CurveFittingDialog.o 0x6c000ba9fa: DW_AT_specification(0x00013cbc) has no decl
...
--------------------------

Our Qt 5.4.1 has been compiled using a command like:

echo yes | MAKEFLAGS=-j16 QMAKESPEC=/qtbuild/qt/mkspecs/unsupported/macx-clang  ../../qt/configure -debug-and-release -opensource -no-qt3support -nomake examples -nomake demos -nomake tests -silent -no-sql-mysql -no-webkit -cocoa -arch x86_64 -arch x86 -no-phonon -no-phonon-backend -prefix /qtbuild/install/macosx

--Jim

===============================================

Jim Prouty

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