[clang] [clang][analysis] Fix flaky clang/test/Analysis/live-stmts.cpp test (PR #126913)

[Mikael Holmén via cfe-commits]

mikaelholmen wrote:

> > Unfortunately the test still seems to be flaky. With EXPENSIVE_CHECKS I often see it fail on the RHEL8 x86_64 machines I use.
> > E.g.
> > ```
> > FAIL: Clang :: Analysis/live-stmts.cpp (1 of 1)
> > ******************** TEST 'Clang :: Analysis/live-stmts.cpp' FAILED ********************
> > Exit Code: 1
> > 
> > Command Output (stderr):
> > --
> > RUN: at line 1: /repo/uabelho/main-github/llvm/build-all-expensive/bin/clang -cc1 -internal-isystem /repo/uabelho/main-github/llvm/build-all-expensive/lib/clang/21/include -nostdsysteminc -analyze -analyzer-constraints=range -setup-static-analyzer -w -analyzer-checker=debug.DumpLiveExprs /repo/uabelho/main-github/clang/test/Analysis/live-stmts.cpp 2>&1   | /repo/uabelho/main-github/llvm/build-all-expensive/bin/FileCheck /repo/uabelho/main-github/clang/test/Analysis/live-stmts.cpp
> > + /repo/uabelho/main-github/llvm/build-all-expensive/bin/clang -cc1 -internal-isystem /repo/uabelho/main-github/llvm/build-all-expensive/lib/clang/21/include -nostdsysteminc -analyze -analyzer-constraints=range -setup-static-analyzer -w -analyzer-checker=debug.DumpLiveExprs /repo/uabelho/main-github/clang/test/Analysis/live-stmts.cpp
> > + /repo/uabelho/main-github/llvm/build-all-expensive/bin/FileCheck /repo/uabelho/main-github/clang/test/Analysis/live-stmts.cpp
> > /repo/uabelho/main-github/clang/test/Analysis/live-stmts.cpp:227:16: error: CHECK-EMPTY: is not on the line after the previous match
> > // CHECK-EMPTY:
> >                ^
> > <stdin>:160:1: note: 'next' match was here
> > 
> > ^
> > <stdin>:157:81: note: previous match ended here
> > | `-DeclRefExpr 0x55e1600cec58 '_Bool' lvalue ParmVar 0x55e1600cead8 'b' '_Bool'
> >                                                                                 ^
> > <stdin>:158:1: note: non-matching line after previous match is here
> > `-ImplicitCastExpr 0x55e1600cecb0 '_Bool' <LValueToRValue>
> > ^
> > 
> > Input file: <stdin>
> > Check file: /repo/uabelho/main-github/clang/test/Analysis/live-stmts.cpp
> > 
> > -dump-input=help explains the following input dump.
> > 
> > Input was:
> > <<<<<<
> >            .
> >            .
> >            .
> >          155: BinaryOperator 0x55e1600cecc8 '_Bool' '||' 
> >          156: |-ImplicitCastExpr 0x55e1600cec98 '_Bool' <LValueToRValue> 
> >          157: | `-DeclRefExpr 0x55e1600cec58 '_Bool' lvalue ParmVar 0x55e1600cead8 'b' '_Bool' 
> >          158: `-ImplicitCastExpr 0x55e1600cecb0 '_Bool' <LValueToRValue> 
> >          159:  `-DeclRefExpr 0x55e1600cec78 '_Bool' lvalue ParmVar 0x55e1600cead8 'b' '_Bool' 
> >          160:  
> > empty:227     ! error: match on wrong line
> >          161: ImplicitCastExpr 0x55e1600cec98 '_Bool' <LValueToRValue> 
> >          162: `-DeclRefExpr 0x55e1600cec58 '_Bool' lvalue ParmVar 0x55e1600cead8 'b' '_Bool' 
> >          163:  
> >          164: ImplicitCastExpr 0x55e1600cecb0 '_Bool' <LValueToRValue> 
> >          165: `-DeclRefExpr 0x55e1600cec78 '_Bool' lvalue ParmVar 0x55e1600cead8 'b' '_Bool' 
> >            .
> >            .
> >            .
> > >>>>>>
> > 
> > --
> > 
> > ********************
> > ********************
> > Failed Tests (1):
> >   Clang :: Analysis/live-stmts.cpp
> > ```
> 
> Oh cmmon. :( Could you send me your nonpassing output, the whole one? @mikaelholmen

Yep 
[out.log](https://github.com/user-attachments/files/18779754/out.log)


https://github.com/llvm/llvm-project/pull/126913