Elab bitfields: check size of type <=32bit rather than checking rank (#…

…387) When desugaring a bitfield, allow any integral type that is 32 bits or smaller. Previously this was checking the rank of the type rather than the size. This rank check caused issues with standard headers that declare `uint32_t` to be an `unsigned long` rather than an `unsigned int`. Here, any bitfields declared as `uint32_t` were failing to compile even though they are still actually 32 bits. Co-authored-by: Amos Robinson <[email protected]>
AbsInt · Apr 19, 2021 · 0877e32 · 0877e32
1 parent 45af10b
commit 0877e32
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Showing 4 changed files with 25 additions and 2 deletions.
diff --git a/cparser/Elab.ml b/cparser/Elab.ml
@@ -1001,7 +1001,7 @@ and elab_field_group env = function
             | TInt(ik, _) -> ik
             | TEnum(_, _) -> enum_ikind
             | _ -> ILongLong (* trigger next error message *) in
-          if integer_rank ik > integer_rank IInt then begin
+          if sizeof_ikind ik > sizeof_ikind IInt then begin
             error loc
               "the type of bit-field '%a' must be an integer type no bigger than 'int'" pp_field id;
             None,env

diff --git a/test/regression/Makefile b/test/regression/Makefile
@@ -21,7 +21,7 @@ TESTS=int32 int64 floats floats-basics floats-lit \
 # Can run, but only in compiled mode, and have reference output in Results
 
 TESTS_COMP=attribs1 bitfields1 bitfields2 bitfields3 bitfields4 \
-  bitfields5 bitfields6 bitfields7 bitfields8 \
+  bitfields5 bitfields6 bitfields7 bitfields8 bitfields_uint_t \
   builtins-common builtins-$(ARCH) packedstruct1 packedstruct2 alignas \
   varargs1 varargs2 varargs3 sections alias aligned
 

diff --git a/test/regression/Results/bitfields_uint_t b/test/regression/Results/bitfields_uint_t
@@ -0,0 +1 @@
+x = { a = 1, b = 2, c = 3, d = 4 }
diff --git a/test/regression/bitfields_uint_t.c b/test/regression/bitfields_uint_t.c
@@ -0,0 +1,22 @@
+#include <stdio.h>
+#include <stdint.h>
+
+/* Test that uint32 type synonym works.
+   This previously failed for standard headers where uint32 is defined
+   as a (32-bit) unsigned long. */
+
+struct s {
+  uint32_t a: 1;
+  uint32_t b: 2;
+  uint32_t c: 9;
+  uint32_t d: 20;
+};
+
+struct s x = { 1, 2, 3, 4 };
+
+int main()
+{
+  printf("x = { a = %d, b = %d, c = %d, d = %d }\n", x.a, x.b, x.c, x.d);
+}
+
+