Squash some warnings (#2956)

* restrict -Wno-assume to clang (gcc does not have this warning)

* Add move where possible

Annoyingly this warns for c++17, but will not be necessary with c++20

* Do not partially initialize struct

* Remove unused variable

* Silence unused var warning

It is actually still referenced from an uninstantiated (for now) template

* Use unused var

---------

Co-authored-by: jsmall-nvidia <jsmall@nvidia.com>

5 files changed, 9 insertions, 8 deletions

diff --git a/premake5.lua b/premake5.lua
index 20bb6b364..edcd56b4e 100644
--- a/premake5.lua
+++ b/premake5.lua
@@ -374,8 +374,10 @@ workspace "slang"
         }
     filter { "toolset:gcc*", "language:C++" }
         buildoptions { "-Wno-class-memaccess" }
+    filter { "toolset:clang", "language:C++" }
+        buildoptions { "-Wno-assume" }
     filter { "toolset:clang or gcc*", "language:C++" }
-        buildoptions { "-Wno-reorder", "-Wno-invalid-offsetof", "-Wno-assume" }
+        buildoptions { "-Wno-reorder", "-Wno-invalid-offsetof" }
 
     -- When compiling the debug configuration, we want to turn
     -- optimization off, make sure debug symbols are output,
diff --git a/source/compiler-core/slang-source-embed-util.cpp b/source/compiler-core/slang-source-embed-util.cpp
index ec0c005cf..45fd9c4b3 100644
--- a/source/compiler-core/slang-source-embed-util.cpp
+++ b/source/compiler-core/slang-source-embed-util.cpp
@@ -73,7 +73,7 @@ static bool _isHeaderExtension(const UnownedStringSlice& in)
     // Assume it's a header, and just use the .h extension
     StringBuilder buf;
     buf << path << toSlice(".h");
-    return buf;
+    return std::move(buf);
 }
 
 /* static */SourceEmbedUtil::Style SourceEmbedUtil::getDefaultStyle(const ArtifactDesc& desc)
diff --git a/source/slang/slang-check-impl.h b/source/slang/slang-check-impl.h
index 26c96a72e..e710f93ec 100644
--- a/source/slang/slang-check-impl.h
+++ b/source/slang/slang-check-impl.h
@@ -57,13 +57,13 @@ namespace Slang
         {
             return getRaw() == other.getRaw();
         }
-        static BasicTypeKey invalid() { return BasicTypeKey{ 0xff, 0, 0 }; }
+        static BasicTypeKey invalid() { return BasicTypeKey{ 0xff, 0, 0, 0, 0, 0 }; }
     };
 
     SLANG_FORCE_INLINE BasicTypeKey makeBasicTypeKey(BaseType baseType, IntegerLiteralValue dim1 = 0, IntegerLiteralValue dim2 = 0)
     {
         SLANG_ASSERT(dim1 >= 0 && dim2 >= 0);
-        return BasicTypeKey{ uint8_t(baseType), uint8_t(dim1), uint8_t(dim2) };
+        return BasicTypeKey{ uint8_t(baseType), uint8_t(dim1), uint8_t(dim2), 0, 0, 0 };
     }
 
     inline BasicTypeKey makeBasicTypeKey(Type* typeIn, Expr* exprIn = nullptr)
diff --git a/source/slang/slang-ir-autodiff-transpose.h b/source/slang/slang-ir-autodiff-transpose.h
index a0f888931..843612df9 100644
--- a/source/slang/slang-ir-autodiff-transpose.h
+++ b/source/slang/slang-ir-autodiff-transpose.h
@@ -2295,8 +2295,8 @@ struct DiffTransposePass
 
         if (auto vectorType = as<IRVectorType>(baseType))
         {
-            IRInst* elementCountInst = as<IRVectorType>(baseType)->getElementCount();
-            elementType = as<IRVectorType>(baseType)->getElementType();
+            IRInst* elementCountInst = vectorType->getElementCount();
+            elementType = vectorType->getElementType();
             primalElementType = as<IRVectorType>(aggPrimalType)->getElementType();
             SLANG_ASSERT(as<IRIntLit>(elementCountInst));
             elementCount = as<IRIntLit>(elementCountInst)->getValue();
diff --git a/source/slang/slang-lower-to-ir.cpp b/source/slang/slang-lower-to-ir.cpp
index cb2c9129a..c70cdb948 100644
--- a/source/slang/slang-lower-to-ir.cpp
+++ b/source/slang/slang-lower-to-ir.cpp
@@ -872,7 +872,7 @@ static LoweredValInfo _emitCallToAccessor(
     /// encapsulates the reference to the storage so that downstream
     /// code can decide which accessor(s) to invoke.
     ///
-
+[[maybe_unused]]
 static LoweredValInfo lowerStorageReference(
     IRGenContext*           context,
     IRType*                 type,
@@ -1448,7 +1448,6 @@ struct ValLoweringVisitor : ValVisitor<ValLoweringVisitor, LoweredValInfo, Lower
 
     LoweredValInfo visitTypeCastIntVal(TypeCastIntVal* val)
     {
-        TryClauseEnvironment tryEnv;
         auto baseVal = lowerVal(context, val->base);
         SLANG_ASSERT(baseVal.flavor == LoweredValInfo::Flavor::Simple);
         auto type = lowerType(context, val->type);