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-rw-r--r--include/clang/Basic/DiagnosticSemaKinds.td8
-rw-r--r--include/clang/Sema/Sema.h4
-rw-r--r--lib/Sema/SemaChecking.cpp61
-rw-r--r--lib/Sema/SemaType.cpp7
-rw-r--r--test/Sema/static-array.c31
5 files changed, 111 insertions, 0 deletions
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 2662a19691..33175a29e5 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -2716,6 +2716,9 @@ def ext_typecheck_zero_array_size : Extension<
"zero size arrays are an extension">;
def err_typecheck_zero_array_size : Error<
"zero-length arrays are not permitted in C++">;
+def warn_typecheck_zero_static_array_size : Warning<
+ "'static' has no effect on zero-length arrays">,
+ InGroup<DiagGroup<"array-bounds">>;
def err_at_least_one_initializer_needed_to_size_array : Error<
"at least one initializer value required to size array">;
def err_array_size_non_int : Error<"size of array has non-integer type %0">;
@@ -4509,6 +4512,11 @@ def warn_format_mix_positional_nonpositional_args : Warning<
def warn_null_arg : Warning<
"null passed to a callee which requires a non-null argument">,
InGroup<NonNull>;
+def warn_static_array_too_small : Warning<
+ "array argument is too small; contains %0 elements, callee requires at least %1">,
+ InGroup<DiagGroup<"array-bounds">>;
+def note_callee_static_array : Note<
+ "callee declares array parameter as static here">;
def warn_empty_format_string : Warning<
"format string is empty">, InGroup<FormatZeroLength>;
def warn_format_string_is_wide_literal : Warning<
diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index 775dc1283d..4f244db737 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -6103,6 +6103,10 @@ private:
const Expr * const *ExprArgs,
SourceLocation CallSiteLoc);
+ void CheckStaticArrayArguments(const FunctionDecl *FDecl,
+ const Expr * const *ExprArgs,
+ SourceLocation CallSiteLoc);
+
void CheckPrintfScanfArguments(const CallExpr *TheCall, bool HasVAListArg,
unsigned format_idx, unsigned firstDataArg,
bool isPrintf);
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 310138354b..329adf89e8 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -360,6 +360,9 @@ bool Sema::CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall) {
TheCall->getCallee()->getLocStart());
}
+ CheckStaticArrayArguments(FDecl, TheCall->getArgs(),
+ TheCall->getCallee()->getLocStart());
+
// Builtin handling
int CMF = -1;
switch (FDecl->getBuiltinID()) {
@@ -1362,6 +1365,64 @@ Sema::CheckNonNullArguments(const NonNullAttr *NonNull,
}
}
+static void DiagnoseCalleeStaticArrayParam(Sema &S, ParmVarDecl *PVD) {
+ TypeLoc TL = PVD->getTypeSourceInfo()->getTypeLoc();
+ if (ArrayTypeLoc *ATL = dyn_cast<ArrayTypeLoc>(&TL))
+ S.Diag(PVD->getLocation(), diag::note_callee_static_array)
+ << ATL->getLocalSourceRange();
+}
+
+/// CheckStaticArrayArguments - Check that each argument corresponding to a
+/// static array parameter is non-null, and that if it is formed by
+/// array-to-pointer decay, the underlying array is sufficiently large.
+///
+/// C99 6.7.5.3p7: If the keyword static also appears within the [ and ] of the
+/// array type derivation, then for each call to the function, the value of the
+/// corresponding actual argument shall provide access to the first element of
+/// an array with at least as many elements as specified by the size expression.
+void
+Sema::CheckStaticArrayArguments(const FunctionDecl *FDecl,
+ const Expr * const *ExprArgs,
+ SourceLocation CallSiteLoc) {
+ // Static array parameters are not supported in C++.
+ if (getLangOptions().CPlusPlus)
+ return;
+
+ for (FunctionDecl::param_const_iterator i = FDecl->param_begin(),
+ e = FDecl->param_end(); i != e; ++i, ++ExprArgs) {
+ const Expr *ArgExpr = *ExprArgs;
+ QualType OrigTy = (*i)->getOriginalType();
+
+ const ArrayType *AT = Context.getAsArrayType(OrigTy);
+ if (!AT || AT->getSizeModifier() != ArrayType::Static)
+ continue;
+
+ if (ArgExpr->isNullPointerConstant(Context,
+ Expr::NPC_NeverValueDependent)) {
+ Diag(CallSiteLoc, diag::warn_null_arg) << ArgExpr->getSourceRange();
+ DiagnoseCalleeStaticArrayParam(*this, *i);
+ continue;
+ }
+
+ const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT);
+ if (!CAT)
+ continue;
+
+ const ConstantArrayType *ArgCAT =
+ Context.getAsConstantArrayType(ArgExpr->IgnoreParenImpCasts()->getType());
+ if (!ArgCAT)
+ continue;
+
+ if (ArgCAT->getSize().ult(CAT->getSize())) {
+ Diag(CallSiteLoc, diag::warn_static_array_too_small)
+ << ArgExpr->getSourceRange()
+ << (unsigned) ArgCAT->getSize().getZExtValue()
+ << (unsigned) CAT->getSize().getZExtValue();
+ DiagnoseCalleeStaticArrayParam(*this, *i);
+ }
+ }
+}
+
/// CheckPrintfScanfArguments - Check calls to printf and scanf (and similar
/// functions) for correct use of format strings.
void
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index d3a39967de..fe5b719591 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -1315,6 +1315,13 @@ QualType Sema::BuildArrayType(QualType T, ArrayType::ArraySizeModifier ASM,
isSFINAEContext()? diag::err_typecheck_zero_array_size
: diag::ext_typecheck_zero_array_size)
<< ArraySize->getSourceRange();
+
+ if (ASM == ArrayType::Static) {
+ Diag(ArraySize->getLocStart(),
+ diag::warn_typecheck_zero_static_array_size)
+ << ArraySize->getSourceRange();
+ ASM = ArrayType::Normal;
+ }
} else if (!T->isDependentType() && !T->isVariablyModifiedType() &&
!T->isIncompleteType()) {
// Is the array too large?
diff --git a/test/Sema/static-array.c b/test/Sema/static-array.c
new file mode 100644
index 0000000000..2d4b968dec
--- /dev/null
+++ b/test/Sema/static-array.c
@@ -0,0 +1,31 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+void cat0(int a[static 0]) {} // expected-warning {{'static' has no effect on zero-length arrays}}
+
+void cat(int a[static 3]) {} // expected-note 2 {{callee declares array parameter as static here}}
+
+typedef int i3[static 3];
+void tcat(i3 a) {}
+
+void vat(int i, int a[static i]) {} // expected-note {{callee declares array parameter as static here}}
+
+void f(int *p) {
+ int a[2], b[3], c[4];
+
+ cat0(0);
+
+ cat(0); // expected-warning {{null passed to a callee which requires a non-null argument}}
+ cat(a); // expected-warning {{array argument is too small; contains 2 elements, callee requires at least 3}}
+ cat(b);
+ cat(c);
+ cat(p);
+
+ tcat(0); // expected-warning {{null passed to a callee which requires a non-null argument}}
+ tcat(a); // expected-warning {{array argument is too small; contains 2 elements, callee requires at least 3}}
+ tcat(b);
+ tcat(c);
+ tcat(p);
+
+ vat(1, 0); // expected-warning {{null passed to a callee which requires a non-null argument}}
+ vat(3, b);
+}
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2025-08-04 06:23:04 +0000