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[Clang][Sema] Switch diagnostics from toString to operator<< for APSInt/APInt #161474

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Merged
merged 5 commits into from
Oct 2, 2025
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[Clang][Sema] Switch diagnostics from toString to operator<< for APSInt/APInt #161474

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0e21cdb
Use operator<< for APSInt/APInt in array access diagnostics
snarang181 Oct 1, 2025
11e7cb8
InsertSeparator=false by default
snarang181 Oct 1, 2025
f7ae8d6
Use new check for some missed cases in SemaChecking.cpp
snarang181 Oct 1, 2025
b01a001
Fix some more tests
snarang181 Oct 1, 2025
5552fa2
Do not truncate to 32-bit in streaming diagnostics
snarang181 Oct 1, 2025
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23 changes: 10 additions & 13 deletions clang/lib/Sema/SemaChecking.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -14881,13 +14881,11 @@ void Sema::CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr,
// Diag message shows element size in bits and in "bytes" (platform-
// dependent CharUnits)
DiagRuntimeBehavior(BaseExpr->getBeginLoc(), BaseExpr,
PDiag(DiagID)
<< toString(index, 10, true) << AddrBits
<< (unsigned)ASTC.toBits(*ElemCharUnits)
<< toString(ElemBytes, 10, false)
<< toString(MaxElems, 10, false)
<< (unsigned)MaxElems.getLimitedValue(~0U)
<< IndexExpr->getSourceRange());
PDiag(DiagID) << index << AddrBits
<< (unsigned)ASTC.toBits(*ElemCharUnits)
<< ElemBytes << MaxElems
<< MaxElems.getZExtValue()
<< IndexExpr->getSourceRange());

const NamedDecl *ND = nullptr;
// Try harder to find a NamedDecl to point at in the note.
Expand Down Expand Up @@ -14970,10 +14968,10 @@ void Sema::CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr,
unsigned CastMsg = (!ASE || BaseType == EffectiveType) ? 0 : 1;
QualType CastMsgTy = ASE ? ASE->getLHS()->getType() : QualType();

DiagRuntimeBehavior(
BaseExpr->getBeginLoc(), BaseExpr,
PDiag(DiagID) << toString(index, 10, true) << ArrayTy->desugar()
<< CastMsg << CastMsgTy << IndexExpr->getSourceRange());
DiagRuntimeBehavior(BaseExpr->getBeginLoc(), BaseExpr,
PDiag(DiagID)
<< index << ArrayTy->desugar() << CastMsg
<< CastMsgTy << IndexExpr->getSourceRange());
} else {
unsigned DiagID = diag::warn_array_index_precedes_bounds;
if (!ASE) {
Expand All @@ -14982,8 +14980,7 @@ void Sema::CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr,
}

DiagRuntimeBehavior(BaseExpr->getBeginLoc(), BaseExpr,
PDiag(DiagID) << toString(index, 10, true)
<< IndexExpr->getSourceRange());
PDiag(DiagID) << index << IndexExpr->getSourceRange());
}

const NamedDecl *ND = nullptr;
Expand Down
2 changes: 1 addition & 1 deletion clang/test/AST/ByteCode/const-eval.c
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Expand Up @@ -144,7 +144,7 @@ EVAL_EXPR(52, &pr24622 == (void *)&PR24622);

// We evaluate these by providing 2s' complement semantics in constant
// expressions, like we do for integers.
void *PR28739a = (__int128)(unsigned long)-1 + &PR28739a; // both-warning {{the pointer incremented by 18446744073709551615 refers past the last possible element for an array in 64-bit address space containing 64-bit (8-byte) elements (max possible 2305843009213693952 elements)}}
void *PR28739a = (__int128)(unsigned long)-1 + &PR28739a; // both-warning {{the pointer incremented by 18'446'744'073'709'551'615 refers past the last possible element for an array in 64-bit address space containing 64-bit (8-byte) elements (max possible 2'305'843'009'213'693'952 elements)}}

void *PR28739b = &PR28739b + (__int128)(unsigned long)-1; // both-warning {{refers past the last possible element}}
__int128 PR28739c = (&PR28739c + (__int128)(unsigned long)-1) - &PR28739c; // both-warning {{refers past the last possible element}}
Expand Down
2 changes: 1 addition & 1 deletion clang/test/Sema/const-eval.c
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Expand Up @@ -138,7 +138,7 @@ EVAL_EXPR(52, &pr24622 == (void *)&PR24622);

// We evaluate these by providing 2s' complement semantics in constant
// expressions, like we do for integers.
void *PR28739a = (__int128)(unsigned long)-1 + &PR28739a; // expected-warning {{the pointer incremented by 18446744073709551615 refers past the last possible element for an array in 64-bit address space containing 64-bit (8-byte) elements (max possible 2305843009213693952 elements)}}
void *PR28739a = (__int128)(unsigned long)-1 + &PR28739a; // expected-warning {{the pointer incremented by 18'446'744'073'709'551'615 refers past the last possible element for an array in 64-bit address space containing 64-bit (8-byte) elements (max possible 2'305'843'009'213'693'952 elements)}}
void *PR28739b = &PR28739b + (__int128)(unsigned long)-1; // expected-warning {{refers past the last possible element}}
__int128 PR28739c = (&PR28739c + (__int128)(unsigned long)-1) - &PR28739c; // expected-warning {{refers past the last possible element}}
void *PR28739d = &(&PR28739d)[(__int128)(unsigned long)-1]; // expected-warning {{refers past the last possible element}}
Expand Down
2 changes: 1 addition & 1 deletion clang/test/Sema/integer-overflow.c
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Expand Up @@ -143,7 +143,7 @@ uint64_t check_integer_overflows(int i) {
(__imag__ x) = 4608 * 1024 * 1024;

// expected-warning@+4 {{overflow in expression; result is 536'870'912 with type 'int'}}
// expected-warning@+3 {{array index 536870912 is past the end of the array (that has type 'uint64_t[10]' (aka 'unsigned long long[10]'))}}
// expected-warning@+3 {{array index 536'870'912 is past the end of the array (that has type 'uint64_t[10]' (aka 'unsigned long long[10]'))}}
// expected-note@+1 {{array 'a' declared here}}
uint64_t a[10];
a[4608 * 1024 * 1024] = 1i;
Expand Down
48 changes: 24 additions & 24 deletions clang/test/Sema/unbounded-array-bounds.c
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Expand Up @@ -14,44 +14,44 @@ struct S s[]; // expected-warning {{tentative array definition}} expected-note {
void f1(void) {
++s[3].a;
++s[7073650413200313099].b;
// addr16-warning@-1 {{array index 7073650413200313099 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3449 elements)}}
// addr32-warning@-2 {{array index 7073650413200313099 refers past the last possible element for an array in 32-bit address space containing 192-bit (24-byte) elements (max possible 178956970 elements)}}
// addr64-warning@-3 {{array index 7073650413200313099 refers past the last possible element for an array in 64-bit address space containing 256-bit (32-byte) elements (max possible 576460752303423488 elements)}}
// addr16-warning@-1 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3'449 elements)}}
// addr32-warning@-2 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 32-bit address space containing 192-bit (24-byte) elements (max possible 178'956'970 elements)}}
// addr64-warning@-3 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 64-bit address space containing 256-bit (32-byte) elements (max possible 576'460'752'303'423'488 elements)}}
++s[7073650].c;
// addr16-warning@-1 {{array index 7073650 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3449 elements)}}
// addr16-warning@-1 {{array index 7'073'650 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3'449 elements)}}
}

long long ll[]; // expected-warning {{tentative array definition}} expected-note {{declared here}} addr16-note {{declared here}} addr32-note {{declared here}}

void f2(void) {
++ll[3];
++ll[2705843009213693952];
// addr16-warning@-1 {{array index 2705843009213693952 refers past the last possible element for an array in 16-bit address space containing 64-bit (8-byte) elements (max possible 8192 elements)}}
// addr32-warning@-2 {{array index 2705843009213693952 refers past the last possible element for an array in 32-bit address space containing 64-bit (8-byte) elements (max possible 536870912 elements)}}
// addr64-warning@-3 {{array index 2705843009213693952 refers past the last possible element for an array in 64-bit address space containing 64-bit (8-byte) elements (max possible 2305843009213693952 elements)}}
// addr16-warning@-1 {{array index 2'705'843'009'213'693'952 refers past the last possible element for an array in 16-bit address space containing 64-bit (8-byte) elements (max possible 8'192 elements)}}
// addr32-warning@-2 {{array index 2'705'843'009'213'693'952 refers past the last possible element for an array in 32-bit address space containing 64-bit (8-byte) elements (max possible 536'870'912 elements)}}
// addr64-warning@-3 {{array index 2'705'843'009'213'693'952 refers past the last possible element for an array in 64-bit address space containing 64-bit (8-byte) elements (max possible 2'305'843'009'213'693'952 elements)}}
++ll[847073650];
// addr16-warning@-1 {{array index 847073650 refers past the last possible element for an array in 16-bit address space containing 64-bit (8-byte) elements (max possible 8192 elements)}}
// addr32-warning@-2 {{array index 847073650 refers past the last possible element for an array in 32-bit address space containing 64-bit (8-byte) elements (max possible 536870912 elements)}}
// addr16-warning@-1 {{array index 847'073'650 refers past the last possible element for an array in 16-bit address space containing 64-bit (8-byte) elements (max possible 8'192 elements)}}
// addr32-warning@-2 {{array index 847'073'650 refers past the last possible element for an array in 32-bit address space containing 64-bit (8-byte) elements (max possible 536'870'912 elements)}}
}

void f3(struct S p[]) { // expected-note {{declared here}} addr16-note {{declared here}}
++p[3].a;
++p[7073650413200313099].b;
// addr16-warning@-1 {{array index 7073650413200313099 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3449 elements)}}
// addr32-warning@-2 {{array index 7073650413200313099 refers past the last possible element for an array in 32-bit address space containing 192-bit (24-byte) elements (max possible 178956970 elements)}}
// addr64-warning@-3 {{array index 7073650413200313099 refers past the last possible element for an array in 64-bit address space containing 256-bit (32-byte) elements (max possible 576460752303423488 elements)}}
// addr16-warning@-1 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3'449 elements)}}
// addr32-warning@-2 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 32-bit address space containing 192-bit (24-byte) elements (max possible 178'956'970 elements)}}
// addr64-warning@-3 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 64-bit address space containing 256-bit (32-byte) elements (max possible 576'460'752'303'423'488 elements)}}
++p[7073650].c;
// addr16-warning@-1 {{array index 7073650 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3449 elements)}}
// addr16-warning@-1 {{array index 7'073'650 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3'449 elements)}}
}

void f4(struct S *p) { // expected-note {{declared here}} addr16-note {{declared here}}
p += 3;
p += 7073650413200313099;
// addr16-warning@-1 {{the pointer incremented by 7073650413200313099 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3449 elements)}}
// addr32-warning@-2 {{the pointer incremented by 7073650413200313099 refers past the last possible element for an array in 32-bit address space containing 192-bit (24-byte) elements (max possible 178956970 elements)}}
// addr64-warning@-3 {{the pointer incremented by 7073650413200313099 refers past the last possible element for an array in 64-bit address space containing 256-bit (32-byte) elements (max possible 576460752303423488 elements)}}
// addr16-warning@-1 {{the pointer incremented by 7'073'650'413'200'313'099 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3'449 elements)}}
// addr32-warning@-2 {{the pointer incremented by 7'073'650'413'200'313'099 refers past the last possible element for an array in 32-bit address space containing 192-bit (24-byte) elements (max possible 178'956'970 elements)}}
// addr64-warning@-3 {{the pointer incremented by 7'073'650'413'200'313'099 refers past the last possible element for an array in 64-bit address space containing 256-bit (32-byte) elements (max possible 576'460'752'303'423'488 elements)}}
p += 7073650;
// addr16-warning@-1 {{the pointer incremented by 7073650 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3449 elements)}}
// addr16-warning@-1 {{the pointer incremented by 7'073'650 refers past the last possible element for an array in 16-bit address space containing 152-bit (19-byte) elements (max possible 3'449 elements)}}
}

struct BQ {
Expand All @@ -63,7 +63,7 @@ struct BQ bq[]; // expected-warning {{tentative array definition}} addr16-note {
void f5(void) {
++bq[0].bigblock[0].a;
++bq[1].bigblock[0].a;
// addr16-warning@-1 {{array index 1 refers past the last possible element for an array in 16-bit address space containing 497952-bit (62244-byte) elements (max possible 1 element)}}
// addr16-warning@-1 {{array index 1 refers past the last possible element for an array in 16-bit address space containing 497952-bit (62'244-byte) elements (max possible 1 element)}}
}

void f6(void) {
Expand Down Expand Up @@ -102,15 +102,15 @@ struct {

void fam_ily() {
++fam.tail[7073650413200313099];
// addr16-warning@-1 {{array index 7073650413200313099 refers past the last possible element for an array in 16-bit address space containing 8-bit (1-byte) elements (max possible 65536 elements)}}
// addr32-warning@-2 {{array index 7073650413200313099 refers past the last possible element for an array in 32-bit address space containing 8-bit (1-byte) elements (max possible 4294967296 elements)}}
// addr16-warning@-1 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 16-bit address space containing 8-bit (1-byte) elements (max possible 65'536 elements)}}
// addr32-warning@-2 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 32-bit address space containing 8-bit (1-byte) elements (max possible 4'294'967'296 elements)}}
// No warning for addr64 because the array index is inbound in that case.
++fam0.tail[7073650413200313099];
// addr16-warning@-1 {{array index 7073650413200313099 refers past the last possible element for an array in 16-bit address space containing 8-bit (1-byte) elements (max possible 65536 elements)}}
// addr32-warning@-2 {{array index 7073650413200313099 refers past the last possible element for an array in 32-bit address space containing 8-bit (1-byte) elements (max possible 4294967296 elements)}}
// addr16-warning@-1 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 16-bit address space containing 8-bit (1-byte) elements (max possible 65'536 elements)}}
// addr32-warning@-2 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 32-bit address space containing 8-bit (1-byte) elements (max possible 4'294'967'296 elements)}}
// No warning for addr64 because the array index is inbound in that case.
++fam1.tail[7073650413200313099];
// addr16-warning@-1 {{array index 7073650413200313099 refers past the last possible element for an array in 16-bit address space containing 8-bit (1-byte) elements (max possible 65536 elements)}}
// addr32-warning@-2 {{array index 7073650413200313099 refers past the last possible element for an array in 32-bit address space containing 8-bit (1-byte) elements (max possible 4294967296 elements)}}
// addr16-warning@-1 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 16-bit address space containing 8-bit (1-byte) elements (max possible 65'536 elements)}}
// addr32-warning@-2 {{array index 7'073'650'413'200'313'099 refers past the last possible element for an array in 32-bit address space containing 8-bit (1-byte) elements (max possible 4'294'967'296 elements)}}
// No warning for addr64 because the array index is inbound in that case.
}
4 changes: 2 additions & 2 deletions clang/test/SemaCXX/array-bounds.cpp
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Expand Up @@ -237,7 +237,7 @@ void test_pr10771() {
((char*)foo)[sizeof(foo) - 1] = '\0'; // no-warning
*(((char*)foo) + sizeof(foo) - 1) = '\0'; // no-warning

((char*)foo)[sizeof(foo)] = '\0'; // expected-warning {{array index 32768 is past the end of the array (that has type 'double[4096]', cast to 'char *')}}
((char*)foo)[sizeof(foo)] = '\0'; // expected-warning {{array index 32'768 is past the end of the array (that has type 'double[4096]', cast to 'char *')}}

// TODO: This should probably warn, too.
*(((char*)foo) + sizeof(foo)) = '\0'; // no-warning
Expand All @@ -248,7 +248,7 @@ int test_pr11007_aux(const char * restrict, ...);
// Test checking with varargs.
void test_pr11007() {
double a[5]; // expected-note {{array 'a' declared here}}
test_pr11007_aux("foo", a[1000]); // expected-warning {{array index 1000 is past the end of the array (that has type 'double[5]')}}
test_pr11007_aux("foo", a[1000]); // expected-warning {{array index 1'000 is past the end of the array (that has type 'double[5]')}}
}

void test_rdar10916006(void)
Expand Down
2 changes: 1 addition & 1 deletion clang/test/SemaCXX/constant-expression-cxx14.cpp
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Expand Up @@ -1047,7 +1047,7 @@ constexpr int S = sum(Cs); // expected-error{{must be initialized by a constant
constexpr void PR28739(int n) { // cxx14_20-error {{never produces a constant}}
int *p = &n; // expected-note {{array 'p' declared here}}
p += (__int128)(unsigned long)-1; // cxx14_20-note {{cannot refer to element 18446744073709551615 of non-array object in a constant expression}}
// expected-warning@-1 {{the pointer incremented by 18446744073709551615 refers past the last possible element for an array in 64-bit address space containing 32-bit (4-byte) elements (max possible 4611686018427387904 elements)}}
// expected-warning@-1 {{the pointer incremented by 18'446'744'073'709'551'615 refers past the last possible element for an array in 64-bit address space containing 32-bit (4-byte) elements (max possible 4'611'686'018'427'387'904 elements)}}
}

constexpr void Void(int n) {
Expand Down
2 changes: 1 addition & 1 deletion clang/test/SemaCXX/integer-overflow.cpp
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Expand Up @@ -171,7 +171,7 @@ uint64_t check_integer_overflows(int i) { //expected-note 0+{{declared here}}
uint64_t a[10];
a[4608 * 1024 * 1024] = 1;
#if __cplusplus < 201103L
// expected-warning@-2 {{array index 536870912 is past the end of the array (that has type 'uint64_t[10]' (aka 'unsigned long long[10]'))}}
// expected-warning@-2 {{array index 536'870'912 is past the end of the array (that has type 'uint64_t[10]' (aka 'unsigned long long[10]'))}}
// expected-note@-4 {{array 'a' declared here}}
#endif

Expand Down