ahatanak created this revision.
ahatanak added reviewers: rsmith, doug.gregor.
ahatanak added a subscriber: cfe-commits.
This patch silences an incorrect warning that is issued when a function pointer
is cast to another function pointer type. The warning gets issued because
alignments of the source and destination do not match in Sema::CheckCastAlign,
which happens because ASTContext::getTypeInfoImpl and ASTContext::getDeclAlign
return different values for functions (the former returns 4 while the latter
returns 1).
https://reviews.llvm.org/D27478
Files:
lib/AST/ASTContext.cpp
test/Sema/warn-cast-align.c
Index: test/Sema/warn-cast-align.c
===================================================================
--- test/Sema/warn-cast-align.c
+++ test/Sema/warn-cast-align.c
@@ -59,3 +59,11 @@
i = (int *)&s.s0;
i = (int *)a;
}
+
+// No warnings.
+typedef int (*FnTy)(void);
+unsigned int func5(void);
+
+FnTy test5(void) {
+ return (FnTy)&func5;
+}
Index: lib/AST/ASTContext.cpp
===================================================================
--- lib/AST/ASTContext.cpp
+++ lib/AST/ASTContext.cpp
@@ -1501,7 +1501,9 @@
Align = std::min(Align, FieldAlign);
}
- }
+ } else if (isa<FunctionDecl>(VD))
+ // GCC extension: alignment of functions is 32 bits
+ Align = 32;
}
return toCharUnitsFromBits(Align);
Index: test/Sema/warn-cast-align.c
===================================================================
--- test/Sema/warn-cast-align.c
+++ test/Sema/warn-cast-align.c
@@ -59,3 +59,11 @@
i = (int *)&s.s0;
i = (int *)a;
}
+
+// No warnings.
+typedef int (*FnTy)(void);
+unsigned int func5(void);
+
+FnTy test5(void) {
+ return (FnTy)&func5;
+}
Index: lib/AST/ASTContext.cpp
===================================================================
--- lib/AST/ASTContext.cpp
+++ lib/AST/ASTContext.cpp
@@ -1501,7 +1501,9 @@
Align = std::min(Align, FieldAlign);
}
- }
+ } else if (isa<FunctionDecl>(VD))
+ // GCC extension: alignment of functions is 32 bits
+ Align = 32;
}
return toCharUnitsFromBits(Align);
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