diff --git a/gn/sksl_tests.gni b/gn/sksl_tests.gni
index 5a18df93c2..6258e1878b 100644
--- a/gn/sksl_tests.gni
+++ b/gn/sksl_tests.gni
@@ -109,6 +109,7 @@ sksl_error_tests = [
   "/sksl/errors/Ossfuzz38560.sksl",
   "/sksl/errors/Ossfuzz38865.sksl",
   "/sksl/errors/Ossfuzz38944.sksl",
+  "/sksl/errors/Ossfuzz39000.sksl",
   "/sksl/errors/OverflowFloatLiteral.sksl",
   "/sksl/errors/OverflowIntLiteral.sksl",
   "/sksl/errors/OverflowInt64Literal.sksl",
diff --git a/resources/sksl/errors/Ossfuzz39000.sksl b/resources/sksl/errors/Ossfuzz39000.sksl
new file mode 100644
index 0000000000..6a4e5057fd
--- /dev/null
+++ b/resources/sksl/errors/Ossfuzz39000.sksl
@@ -0,0 +1,2 @@
+q { int y; };
+G { int q=_; };
diff --git a/src/sksl/SkSLIRGenerator.cpp b/src/sksl/SkSLIRGenerator.cpp
index f430bf30f1..41383e1405 100644
--- a/src/sksl/SkSLIRGenerator.cpp
+++ b/src/sksl/SkSLIRGenerator.cpp
@@ -794,7 +794,7 @@ std::unique_ptr<SkSL::InterfaceBlock> IRGenerator::convertInterfaceBlock(const A
         }
     }
     std::unique_ptr<SkSL::InterfaceBlock> result = std::make_unique<SkSL::InterfaceBlock>(
-            intf.fOffset, var, id.fTypeName, id.fInstanceName, arraySize, symbols);
+            intf.fOffset, *var, id.fTypeName, id.fInstanceName, arraySize, symbols);
     this->scanInterfaceBlock(*result);
     return result;
 }
diff --git a/src/sksl/SkSLRehydrator.cpp b/src/sksl/SkSLRehydrator.cpp
index 5d10c829dc..b9fab8bd59 100644
--- a/src/sksl/SkSLRehydrator.cpp
+++ b/src/sksl/SkSLRehydrator.cpp
@@ -285,7 +285,7 @@ std::unique_ptr<ProgramElement> Rehydrator::element() {
             skstd::string_view typeName = this->readString();
             skstd::string_view instanceName = this->readString();
             int arraySize = this->readS8();
-            return std::make_unique<InterfaceBlock>(/*offset=*/-1, &var->as<Variable>(), typeName,
+            return std::make_unique<InterfaceBlock>(/*offset=*/-1, var->as<Variable>(), typeName,
                                                     instanceName, arraySize, nullptr);
         }
         case Rehydrator::kVarDeclarations_Command: {
diff --git a/src/sksl/codegen/SkSLSPIRVCodeGenerator.cpp b/src/sksl/codegen/SkSLSPIRVCodeGenerator.cpp
index 4cdd5fd4fd..d42b6e265e 100644
--- a/src/sksl/codegen/SkSLSPIRVCodeGenerator.cpp
+++ b/src/sksl/codegen/SkSLSPIRVCodeGenerator.cpp
@@ -3052,7 +3052,7 @@ SpvId SPIRVCodeGenerator::writeInterfaceBlock(const InterfaceBlock& intf, bool a
                                                intfVar.storage()));
             fSPIRVBonusVariables.insert(modifiedVar);
             InterfaceBlock modifiedCopy(intf.fOffset,
-                                        modifiedVar,
+                                        *modifiedVar,
                                         intf.typeName(),
                                         intf.instanceName(),
                                         intf.arraySize(),
@@ -3459,7 +3459,7 @@ void SPIRVCodeGenerator::writeUniformBuffer(std::shared_ptr<SymbolTable> topLeve
 
     // Create an interface block object for this global variable.
     fUniformBuffer.fInterfaceBlock = std::make_unique<InterfaceBlock>(
-            /*offset=*/-1, fUniformBuffer.fInnerVariable.get(), kUniformBufferName,
+            /*offset=*/-1, *fUniformBuffer.fInnerVariable, kUniformBufferName,
             kUniformBufferName, /*arraySize=*/0, topLevelSymbolTable);
 
     // Generate an interface block and hold onto its ID.
@@ -3528,7 +3528,7 @@ void SPIRVCodeGenerator::addRTFlipUniform(int offset) {
         fProgram.fSymbols->add(std::make_unique<Field>(/*offset=*/-1, intfVar, /*field=*/0));
     }
     InterfaceBlock intf(/*offset=*/-1,
-                        intfVar,
+                        *intfVar,
                         name,
                         /*instanceName=*/"",
                         /*arraySize=*/0,
diff --git a/src/sksl/dsl/DSLCore.cpp b/src/sksl/dsl/DSLCore.cpp
index 4c140b7cc6..bc5b38fc6b 100644
--- a/src/sksl/dsl/DSLCore.cpp
+++ b/src/sksl/dsl/DSLCore.cpp
@@ -230,20 +230,22 @@ public:
         if (!DSLWriter::Settings().fDSLMarkVarsDeclared) {
             DSLWriter::MarkDeclared(var);
         }
-        auto intf = std::make_unique<SkSL::InterfaceBlock>(/*offset=*/-1,
-                DSLWriter::Var(var), typeName, varName, arraySize, DSLWriter::SymbolTable());
-        DSLWriter::IRGenerator().scanInterfaceBlock(*intf);
-        DSLWriter::ProgramElements().push_back(std::move(intf));
-        if (varName.empty()) {
-            const std::vector<SkSL::Type::Field>& structFields = structType->fields();
-            const SkSL::Variable* skslVar = DSLWriter::Var(var);
-            for (size_t i = 0; i < structFields.size(); ++i) {
-                DSLWriter::SymbolTable()->add(std::make_unique<SkSL::Field>(/*offset=*/-1,
-                                                                            skslVar,
-                                                                            i));
+        const SkSL::Variable* skslVar = DSLWriter::Var(var);
+        if (skslVar) {
+            auto intf = std::make_unique<SkSL::InterfaceBlock>(/*offset=*/-1,
+                    *skslVar, typeName, varName, arraySize, DSLWriter::SymbolTable());
+            DSLWriter::IRGenerator().scanInterfaceBlock(*intf);
+            DSLWriter::ProgramElements().push_back(std::move(intf));
+            if (varName.empty()) {
+                const std::vector<SkSL::Type::Field>& structFields = structType->fields();
+                for (size_t i = 0; i < structFields.size(); ++i) {
+                    DSLWriter::SymbolTable()->add(std::make_unique<SkSL::Field>(/*offset=*/-1,
+                                                                                skslVar,
+                                                                                i));
+                }
+            } else {
+                AddToSymbolTable(var);
             }
-        } else {
-            AddToSymbolTable(var);
         }
         GetErrorReporter().reportPendingErrors(pos);
         return var;
diff --git a/src/sksl/ir/SkSLInterfaceBlock.h b/src/sksl/ir/SkSLInterfaceBlock.h
index 0405e2e27d..1665446c1e 100644
--- a/src/sksl/ir/SkSLInterfaceBlock.h
+++ b/src/sksl/ir/SkSLInterfaceBlock.h
@@ -31,7 +31,7 @@ class InterfaceBlock final : public ProgramElement {
 public:
     static constexpr Kind kProgramElementKind = Kind::kInterfaceBlock;
 
-    InterfaceBlock(int offset, const Variable* var, skstd::string_view typeName,
+    InterfaceBlock(int offset, const Variable& var, skstd::string_view typeName,
                    skstd::string_view instanceName, int arraySize,
                    std::shared_ptr<SymbolTable> typeOwner)
     : INHERITED(offset, kProgramElementKind)
@@ -42,11 +42,7 @@ public:
     , fTypeOwner(std::move(typeOwner)) {}
 
     const Variable& variable() const {
-        return *fVariable;
-    }
-
-    void setVariable(const Variable* var) {
-        fVariable = var;
+        return fVariable;
     }
 
     skstd::string_view typeName() const {
@@ -66,7 +62,7 @@ public:
     }
 
     std::unique_ptr<ProgramElement> clone() const override {
-        return std::make_unique<InterfaceBlock>(fOffset, &this->variable(), this->typeName(),
+        return std::make_unique<InterfaceBlock>(fOffset, this->variable(), this->typeName(),
                                                 this->instanceName(), this->arraySize(),
                                                 SymbolTable::WrapIfBuiltin(this->typeOwner()));
     }
@@ -91,7 +87,7 @@ public:
     }
 
 private:
-    const Variable* fVariable;
+    const Variable& fVariable;
     skstd::string_view fTypeName;
     skstd::string_view fInstanceName;
     int fArraySize;
diff --git a/tests/sksl/errors/Ossfuzz39000.glsl b/tests/sksl/errors/Ossfuzz39000.glsl
new file mode 100644
index 0000000000..163e3d437b
--- /dev/null
+++ b/tests/sksl/errors/Ossfuzz39000.glsl
@@ -0,0 +1,4 @@
+### Compilation failed:
+
+error: 2: expected ';', but found '='
+1 error