crash on evaluation of invalid expr

[kadircet]

$ cat preproc.cc
__attribute__((__vector_size__(sizeof(long)))) long m;
const long long t0 = *0;
int a = m - t0;

$ ~/repos/llvm/build/bin/clang -xc++ -std=c++20 preproc.cc
preproc.cc:2:22: error: indirection requires pointer operand ('int' invalid)
    2 | const long long t0 = *0;
      |                      ^~
clang-20: /usr/local/google/home/kadircet/repos/llvm/clang/lib/AST/ExprConstant.cpp:16154: bool clang::Expr::EvaluateAsInt(EvalResult &, const ASTContext &, SideEffectsKind, bool) const: Assertion `!isValueDependent() && "Expression evaluator can't be called on a dependent expression."' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: /usr/local/google/home/kadircet/repos/llvm/build/bin/clang-20 -cc1 -triple x86_64-unknown-linux-gnu -emit-obj -dumpdir a- -disable-free -clear-ast-before-backend -main-file-name preproc.cc -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/usr/local/google/home/kadircet/repos/tmp/clangd_crashes/321217557 -fcoverage-compilation-dir=/usr/local/google/home/kadircet/repos/tmp/clangd_crashes/321217557 -resource-dir /usr/local/google/home/kadircet/repos/llvm/build/lib/clang/20 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/c++/14 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/x86_64-linux-gnu/c++/14 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/c++/14/backward -internal-isystem /usr/local/google/home/kadircet/repos/llvm/build/lib/clang/20/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -std=c++20 -fdeprecated-macro -ferror-limit 19 -fgnuc-version=4.2.1 -fno-implicit-modules -fskip-odr-check-in-gmf -fcxx-exceptions -fexceptions -fcolor-diagnostics -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/preproc-ec90d7.o -x c++ preproc.cc
1.      preproc.cc:3:15: current parser token ';'
 #0 0x00005592888ac528 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /usr/local/google/home/kadircet/repos/llvm/llvm/lib/Support/Unix/Signals.inc:723:13
 #1 0x00005592888aa0fe llvm::sys::RunSignalHandlers() /usr/local/google/home/kadircet/repos/llvm/llvm/lib/Support/Signals.cpp:106:18
 #2 0x00005592888acbd8 SignalHandler(int) /usr/local/google/home/kadircet/repos/llvm/llvm/lib/Support/Unix/Signals.inc:413:1
 #3 0x00007f045b4591a0 (/lib/x86_64-linux-gnu/libc.so.6+0x3d1a0)
 #4 0x00007f045b4a70ec __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
 #5 0x00007f045b459102 gsignal ./signal/../sysdeps/posix/raise.c:27:6
 #6 0x00007f045b4424f2 abort ./stdlib/abort.c:81:7
 #7 0x00007f045b442415 _nl_load_domain ./intl/loadmsgcat.c:1177:9
 #8 0x00007f045b451d32 (/lib/x86_64-linux-gnu/libc.so.6+0x35d32)
 #9 0x000055928c0cafa9 (/usr/local/google/home/kadircet/repos/llvm/build/bin/clang-20+0xb726fa9)
#10 0x000055928b441b7f canConvertIntToOtherIntTy /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:0:29
#11 0x000055928b441b7f tryGCCVectorConvertAndSplat(clang::Sema&, clang::ActionResult<clang::Expr*, true>*, clang::ActionResult<clang::Expr*, true>*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:10009:9
#12 0x000055928b43c2d0 clang::Sema::CheckVectorOperands(clang::ActionResult<clang::Expr*, true>&, clang::ActionResult<clang::Expr*, true>&, clang::SourceLocation, bool, bool, bool, bool, bool) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:0:12
#13 0x000055928b444e04 clang::Sema::CheckSubtractionOperands(clang::ActionResult<clang::Expr*, true>&, clang::ActionResult<clang::Expr*, true>&, clang::SourceLocation, clang::QualType*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:10986:9
#14 0x000055928b450ad6 clang::Sema::CreateBuiltinBinOp(clang::SourceLocation, clang::BinaryOperatorKind, clang::Expr*, clang::Expr*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:0:16
#15 0x000055928b41ec46 clang::Sema::ActOnBinOp(clang::Scope*, clang::SourceLocation, clang::tok::TokenKind, clang::Expr*, clang::Expr*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:15083:1
#16 0x000055928aedce67 clang::Parser::ParseRHSOfBinaryExpression(clang::ActionResult<clang::Expr*, true>, clang::prec::Level) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/ParseExpr.cpp:662:21
#17 0x000055928aedbb0d clang::Parser::ParseAssignmentExpression(clang::Parser::TypeCastState) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/ParseExpr.cpp:0:10
#18 0x000055928af33f54 clang::Parser::ParseDeclarationAfterDeclaratorAndAttributes(clang::Declarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::ForRangeInit*) /usr/local/google/home/kadircet/repos/llvm/clang/include/clang/Parse/Parser.h:0:14
#19 0x000055928af31150 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::ParsedAttributes&, clang::Parser::ParsedTemplateInfo&, clang::SourceLocation*, clang::Parser::ForRangeInit*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/ParseDecl.cpp:2523:7
#20 0x000055928aeb93d9 clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec&, clang::AccessSpecifier) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/Parser.cpp:0:10
#21 0x000055928aeb8bf2 clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*, clang::AccessSpecifier) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/Parser.cpp:1266:12
#22 0x000055928aeb79d9 clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&, clang::ParsedAttributes&, clang::ParsingDeclSpec*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/Parser.cpp:0:14
#23 0x000055928aeb5a06 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, clang::Sema::ModuleImportState&) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/Parser.cpp:758:10
#24 0x000055928aeb0f5e clang::ParseAST(clang::Sema&, bool, bool) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/ParseAST.cpp:170:5
#25 0x000055928955ba2f clang::FrontendAction::Execute() /usr/local/google/home/kadircet/repos/llvm/clang/lib/Frontend/FrontendAction.cpp:1082:10
#26 0x00005592894c6a3d getPtr /usr/local/google/home/kadircet/repos/llvm/llvm/include/llvm/Support/Error.h:279:42
#27 0x00005592894c6a3d operator bool /usr/local/google/home/kadircet/repos/llvm/llvm/include/llvm/Support/Error.h:242:16
#28 0x00005592894c6a3d clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Frontend/CompilerInstance.cpp:1061:23
#29 0x0000559289643dce clang::ExecuteCompilerInvocation(clang::CompilerInstance*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:280:25
#30 0x000055928612cfeb cc1_main(llvm::ArrayRef<char const*>, char const*, void*) /usr/local/google/home/kadircet/repos/llvm/clang/tools/driver/cc1_main.cpp:285:15
#31 0x00005592861296cd ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) /usr/local/google/home/kadircet/repos/llvm/clang/tools/driver/driver.cpp:215:12
#32 0x0000559286128478 clang_main(int, char**, llvm::ToolContext const&) /usr/local/google/home/kadircet/repos/llvm/clang/tools/driver/driver.cpp:256:12
#33 0x0000559286139c07 main /usr/local/google/home/kadircet/repos/llvm/build/tools/clang/tools/driver/clang-driver.cpp:17:10
#34 0x00007f045b443b8a __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
#35 0x00007f045b443c45 call_init ./csu/../csu/libc-start.c:128:20
#36 0x00007f045b443c45 __libc_start_main ./csu/../csu/libc-start.c:347:5
#37 0x0000559286127021 _start (/usr/local/google/home/kadircet/repos/llvm/build/bin/clang-20+0x5783021)

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: kadir çetinkaya (kadircet)

```cpp $ cat preproc.cc __attribute__((__vector_size__(sizeof(long)))) long m; const long long t0 = *0; int a = m - t0; ```

$ ~/repos/llvm/build/bin/clang -xc++ -std=c++20 preproc.cc
preproc.cc:2:22: error: indirection requires pointer operand ('int' invalid)
    2 | const long long t0 = *0;
      |                      ^~
clang-20: /usr/local/google/home/kadircet/repos/llvm/clang/lib/AST/ExprConstant.cpp:16154: bool clang::Expr::EvaluateAsInt(EvalResult &, const ASTContext &, SideEffectsKind, bool) const: Assertion `!isValueDependent() && "Expression evaluator can't be called on a dependent expression."' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: /usr/local/google/home/kadircet/repos/llvm/build/bin/clang-20 -cc1 -triple x86_64-unknown-linux-gnu -emit-obj -dumpdir a- -disable-free -clear-ast-before-backend -main-file-name preproc.cc -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/usr/local/google/home/kadircet/repos/tmp/clangd_crashes/321217557 -fcoverage-compilation-dir=/usr/local/google/home/kadircet/repos/tmp/clangd_crashes/321217557 -resource-dir /usr/local/google/home/kadircet/repos/llvm/build/lib/clang/20 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/c++/14 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/x86_64-linux-gnu/c++/14 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/c++/14/backward -internal-isystem /usr/local/google/home/kadircet/repos/llvm/build/lib/clang/20/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -std=c++20 -fdeprecated-macro -ferror-limit 19 -fgnuc-version=4.2.1 -fno-implicit-modules -fskip-odr-check-in-gmf -fcxx-exceptions -fexceptions -fcolor-diagnostics -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/preproc-ec90d7.o -x c++ preproc.cc
1.      preproc.cc:3:15: current parser token ';'
 #<!-- -->0 0x00005592888ac528 llvm::sys::PrintStackTrace(llvm::raw_ostream&amp;, int) /usr/local/google/home/kadircet/repos/llvm/llvm/lib/Support/Unix/Signals.inc:723:13
 #<!-- -->1 0x00005592888aa0fe llvm::sys::RunSignalHandlers() /usr/local/google/home/kadircet/repos/llvm/llvm/lib/Support/Signals.cpp:106:18
 #<!-- -->2 0x00005592888acbd8 SignalHandler(int) /usr/local/google/home/kadircet/repos/llvm/llvm/lib/Support/Unix/Signals.inc:413:1
 #<!-- -->3 0x00007f045b4591a0 (/lib/x86_64-linux-gnu/libc.so.6+0x3d1a0)
 #<!-- -->4 0x00007f045b4a70ec __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
 #<!-- -->5 0x00007f045b459102 gsignal ./signal/../sysdeps/posix/raise.c:27:6
 #<!-- -->6 0x00007f045b4424f2 abort ./stdlib/abort.c:81:7
 #<!-- -->7 0x00007f045b442415 _nl_load_domain ./intl/loadmsgcat.c:1177:9
 #<!-- -->8 0x00007f045b451d32 (/lib/x86_64-linux-gnu/libc.so.6+0x35d32)
 #<!-- -->9 0x000055928c0cafa9 (/usr/local/google/home/kadircet/repos/llvm/build/bin/clang-20+0xb726fa9)
#<!-- -->10 0x000055928b441b7f canConvertIntToOtherIntTy /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:0:29
#<!-- -->11 0x000055928b441b7f tryGCCVectorConvertAndSplat(clang::Sema&amp;, clang::ActionResult&lt;clang::Expr*, true&gt;*, clang::ActionResult&lt;clang::Expr*, true&gt;*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:10009:9
#<!-- -->12 0x000055928b43c2d0 clang::Sema::CheckVectorOperands(clang::ActionResult&lt;clang::Expr*, true&gt;&amp;, clang::ActionResult&lt;clang::Expr*, true&gt;&amp;, clang::SourceLocation, bool, bool, bool, bool, bool) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:0:12
#<!-- -->13 0x000055928b444e04 clang::Sema::CheckSubtractionOperands(clang::ActionResult&lt;clang::Expr*, true&gt;&amp;, clang::ActionResult&lt;clang::Expr*, true&gt;&amp;, clang::SourceLocation, clang::QualType*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:10986:9
#<!-- -->14 0x000055928b450ad6 clang::Sema::CreateBuiltinBinOp(clang::SourceLocation, clang::BinaryOperatorKind, clang::Expr*, clang::Expr*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:0:16
#<!-- -->15 0x000055928b41ec46 clang::Sema::ActOnBinOp(clang::Scope*, clang::SourceLocation, clang::tok::TokenKind, clang::Expr*, clang::Expr*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Sema/SemaExpr.cpp:15083:1
#<!-- -->16 0x000055928aedce67 clang::Parser::ParseRHSOfBinaryExpression(clang::ActionResult&lt;clang::Expr*, true&gt;, clang::prec::Level) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/ParseExpr.cpp:662:21
#<!-- -->17 0x000055928aedbb0d clang::Parser::ParseAssignmentExpression(clang::Parser::TypeCastState) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/ParseExpr.cpp:0:10
#<!-- -->18 0x000055928af33f54 clang::Parser::ParseDeclarationAfterDeclaratorAndAttributes(clang::Declarator&amp;, clang::Parser::ParsedTemplateInfo const&amp;, clang::Parser::ForRangeInit*) /usr/local/google/home/kadircet/repos/llvm/clang/include/clang/Parse/Parser.h:0:14
#<!-- -->19 0x000055928af31150 clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&amp;, clang::DeclaratorContext, clang::ParsedAttributes&amp;, clang::Parser::ParsedTemplateInfo&amp;, clang::SourceLocation*, clang::Parser::ForRangeInit*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/ParseDecl.cpp:2523:7
#<!-- -->20 0x000055928aeb93d9 clang::Parser::ParseDeclOrFunctionDefInternal(clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;, clang::ParsingDeclSpec&amp;, clang::AccessSpecifier) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/Parser.cpp:0:10
#<!-- -->21 0x000055928aeb8bf2 clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;, clang::ParsingDeclSpec*, clang::AccessSpecifier) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/Parser.cpp:1266:12
#<!-- -->22 0x000055928aeb79d9 clang::Parser::ParseExternalDeclaration(clang::ParsedAttributes&amp;, clang::ParsedAttributes&amp;, clang::ParsingDeclSpec*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/Parser.cpp:0:14
#<!-- -->23 0x000055928aeb5a06 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr&lt;clang::DeclGroupRef&gt;&amp;, clang::Sema::ModuleImportState&amp;) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/Parser.cpp:758:10
#<!-- -->24 0x000055928aeb0f5e clang::ParseAST(clang::Sema&amp;, bool, bool) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Parse/ParseAST.cpp:170:5
#<!-- -->25 0x000055928955ba2f clang::FrontendAction::Execute() /usr/local/google/home/kadircet/repos/llvm/clang/lib/Frontend/FrontendAction.cpp:1082:10
#<!-- -->26 0x00005592894c6a3d getPtr /usr/local/google/home/kadircet/repos/llvm/llvm/include/llvm/Support/Error.h:279:42
#<!-- -->27 0x00005592894c6a3d operator bool /usr/local/google/home/kadircet/repos/llvm/llvm/include/llvm/Support/Error.h:242:16
#<!-- -->28 0x00005592894c6a3d clang::CompilerInstance::ExecuteAction(clang::FrontendAction&amp;) /usr/local/google/home/kadircet/repos/llvm/clang/lib/Frontend/CompilerInstance.cpp:1061:23
#<!-- -->29 0x0000559289643dce clang::ExecuteCompilerInvocation(clang::CompilerInstance*) /usr/local/google/home/kadircet/repos/llvm/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:280:25
#<!-- -->30 0x000055928612cfeb cc1_main(llvm::ArrayRef&lt;char const*&gt;, char const*, void*) /usr/local/google/home/kadircet/repos/llvm/clang/tools/driver/cc1_main.cpp:285:15
#<!-- -->31 0x00005592861296cd ExecuteCC1Tool(llvm::SmallVectorImpl&lt;char const*&gt;&amp;, llvm::ToolContext const&amp;) /usr/local/google/home/kadircet/repos/llvm/clang/tools/driver/driver.cpp:215:12
#<!-- -->32 0x0000559286128478 clang_main(int, char**, llvm::ToolContext const&amp;) /usr/local/google/home/kadircet/repos/llvm/clang/tools/driver/driver.cpp:256:12
#<!-- -->33 0x0000559286139c07 main /usr/local/google/home/kadircet/repos/llvm/build/tools/clang/tools/driver/clang-driver.cpp:17:10
#<!-- -->34 0x00007f045b443b8a __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
#<!-- -->35 0x00007f045b443c45 call_init ./csu/../csu/libc-start.c:128:20
#<!-- -->36 0x00007f045b443c45 __libc_start_main ./csu/../csu/libc-start.c:347:5
#<!-- -->37 0x0000559286127021 _start (/usr/local/google/home/kadircet/repos/llvm/build/bin/clang-20+0x5783021)

[AaronBallman]

Confirmed: https://godbolt.org/z/xx73GPY7q

[a-tarasyuk]

@AaronBallman I've noticed that conversions to floats also lead to assertion failures., all cases which trigger canConvertIntTyToFloatTy/canConvertIntToOtherIntTy...

llvm-project/clang/test/SemaCXX/vector.cpp

Lines 776 to 788 in d8bed3f

	namespace GH105486 {
	__attribute__((__vector_size__(sizeof(double)))) double a;
	double b = a - (long)(*0); // expected-error {{indirection requires pointer operand ('int' invalid)}} \
	// expected-error {{cannot initialize a variable of type 'double' with an rvalue of type '__attribute__((__vector_size__(1 * sizeof(double)))) double' (vector of 1 'double' value)}}
	__attribute__((__vector_size__(sizeof(long)))) long c;
	long d = c - (long)(*0); // expected-error {{indirection requires pointer operand ('int' invalid)}} \
	// expected-error {{cannot initialize a variable of type 'long' with an rvalue of type '__attribute__((__vector_size__(1 * sizeof(long)))) long' (vector of 1 'long' value)}}
	const long long e = *0; // expected-error {{indirection requires pointer operand ('int' invalid)}}
	double f = a - e; // expected-error {{cannot initialize a variable of type 'double' with an rvalue of type '__attribute__((__vector_size__(1 * sizeof(double)))) double' (vector of 1 'double' value)}}
	int h = c - e; // expected-error {{cannot initialize a variable of type 'int' with an rvalue of type '__attribute__((__vector_size__(1 * sizeof(long)))) long' (vector of 1 'long' value)}}
	}

Is it okay to prevent value-dependent conversions in the canConvertIntToOtherIntTy and canConvertIntTyToFloatTy (to prevent int evaluation) helpers, or should we avoid vector conversions in these cases at all? Thanks