diff options
Diffstat (limited to 'debian/patches/gcc-elfv2-abi-warn2.diff')
| -rw-r--r-- | debian/patches/gcc-elfv2-abi-warn2.diff | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/debian/patches/gcc-elfv2-abi-warn2.diff b/debian/patches/gcc-elfv2-abi-warn2.diff new file mode 100644 index 0000000..5309998 --- /dev/null +++ b/debian/patches/gcc-elfv2-abi-warn2.diff @@ -0,0 +1,106 @@ +# DP: ppc64el, fix aggregate alignment ABI issue + +this is the variant intended for the 4.8/4.9 branches of the patch: +https://gcc.gnu.org/ml/gcc-patches/2014-07/msg00995.html + +As discussed, it does *not* actually change ABI, but only warn when +encountering a situation where the ABI will change in a future GCC. +(Avoiding the specific term "GCC 4.10" here since I'm not certain +whether the next GCC release will in fact be called that ...) + +Tested on powerpc64-linux and powerpc64le-linux; also verified using +the ABI compat suite (against an unpatched GCC) that this patch does +not change the ABI. + +OK for 4.8/4.9 once the mainline patch is in? + +Bye, +Ulrich + + +gcc/ChangeLog: + + * config/rs6000/rs6000.c (rs6000_function_arg_boundary): Issue + -Wpsabi note when encountering a type where future GCC releases + will apply different alignment requirements. + +gcc/testsuite/ChangeLog: + + * gcc.target/powerpc/ppc64-abi-warn-2.c: New test. + + +--- a/src/gcc/config/rs6000/rs6000.c ++++ b/src/gcc/config/rs6000/rs6000.c +@@ -9180,14 +9180,51 @@ rs6000_function_arg_boundary (enum machi + || (type && TREE_CODE (type) == VECTOR_TYPE + && int_size_in_bytes (type) >= 16)) + return 128; +- else if (((TARGET_MACHO && rs6000_darwin64_abi) +- || DEFAULT_ABI == ABI_ELFv2 +- || (DEFAULT_ABI == ABI_AIX && !rs6000_compat_align_parm)) +- && mode == BLKmode +- && type && TYPE_ALIGN (type) > 64) ++ ++ /* Aggregate types that need > 8 byte alignment are quadword-aligned ++ in the parameter area in the ELFv2 ABI, and in the AIX ABI unless ++ -mcompat-align-parm is used. */ ++ if (((DEFAULT_ABI == ABI_AIX && !rs6000_compat_align_parm) ++ || DEFAULT_ABI == ABI_ELFv2) ++ && type && TYPE_ALIGN (type) > 64) ++ { ++ /* "Aggregate" means any AGGREGATE_TYPE except for single-element ++ or homogeneous float/vector aggregates here. We already handled ++ vector aggregates above, but still need to check for float here. */ ++ bool aggregate_p = (AGGREGATE_TYPE_P (type) ++ && !SCALAR_FLOAT_MODE_P (elt_mode)); ++ ++ /* We used to check for BLKmode instead of the above aggregate type ++ check. Warn when this results in any difference to the ABI. */ ++ if (aggregate_p != (mode == BLKmode)) ++ { ++ static bool warned; ++ if (!warned && warn_psabi) ++ { ++ warned = true; ++ inform (input_location, ++ "the ABI of passing aggregates with %d-byte alignment" ++ " will change in a future GCC release", ++ (int) TYPE_ALIGN (type) / BITS_PER_UNIT); ++ } ++ } ++ ++ /* GCC 4.8/4.9 Note: To avoid any ABI change on a release branch, we ++ keep using the BLKmode check, but warn if there will be differences ++ in future GCC releases. */ ++ if (mode == BLKmode) ++ return 128; ++ } ++ ++ /* Similar for the Darwin64 ABI. Note that for historical reasons we ++ implement the "aggregate type" check as a BLKmode check here; this ++ means certain aggregate types are in fact not aligned. */ ++ if (TARGET_MACHO && rs6000_darwin64_abi ++ && mode == BLKmode ++ && type && TYPE_ALIGN (type) > 64) + return 128; +- else +- return PARM_BOUNDARY; ++ ++ return PARM_BOUNDARY; + } + + /* The offset in words to the start of the parameter save area. */ +--- /dev/null ++++ b/src/gcc/testsuite/gcc.target/powerpc/ppc64-abi-warn-2.c +@@ -0,0 +1,11 @@ ++/* { dg-do compile { target { powerpc*-*-linux* && lp64 } } } */ ++ ++struct test ++ { ++ long a __attribute__((aligned (16))); ++ }; ++ ++void test (struct test a) /* { dg-message "note: the ABI of passing aggregates with 16-byte alignment will change" } */ ++{ ++} ++ |