Unlike C, C++ doesn't mark enums shortened by -fshort-enums as packed.
This makes for undesirable warning differences between C and C++,
e.g. c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early*.c
triggers a warning about a type cast from a pointer to enum that, when
packed, might not be sufficiently aligned.
This change is not enough for that warning to trigger. The tree
expression generated by the C++ front-end is also a little too
complicated for us get to the base pointer. A separate patch takes
care of that.
Regstrapped on x86_64-linux-gnu, also tested on arm-eabi with default
cpu on trunk, and with tms570 on gcc-13. Ok to install?
for gcc/cp/ChangeLog
* decl.cc (finish_enum_value_list): Set TYPE_PACKED if
use_short_enum, and propagate it to variants.
---
gcc/cp/decl.cc | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index 038c5ab71f201..f6d5645d5080f 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -16881,6 +16881,12 @@ finish_enum_value_list (tree enumtype)
/* If -fstrict-enums, still constrain TYPE_MIN/MAX_VALUE. */
if (flag_strict_enums)
set_min_and_max_values_for_integral_type (enumtype, precision, sgn);
+
+ if (use_short_enum)
+ {
+ TYPE_PACKED (enumtype) = use_short_enum;
+ fixup_attribute_variants (enumtype);
+ }
}
else
underlying_type = ENUM_UNDERLYING_TYPE (enumtype);
--
Alexandre Oliva, happy hacker https://FSFLA.org/blogs/lxo/
Free Software Activist GNU Toolchain Engineer
More tolerance and less prejudice are key for inclusion and diversity
Excluding neuro-others for not behaving ""normal"" is *not* inclusive
