http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51483
Bug #: 51483
Summary: [4.7 regression] Ada's cstand.adb:Register_Float_Type
makes invalid assumptions about FP representation
Classification: Unclassified
Product: gcc
Version: 4.7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: ada
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: mi...@it.uu.se
Redirected from PR48835:
Attempting to build an Ada-enabled gcc-4.7 cross to m68k-linux fails with:
/tmp/objdir/./gcc/xgcc -B/tmp/objdir/./gcc/
-B/home/mikpe/pkgs/linux-x86/cross-m68k/m68k-unknown-linux/bin/
-B/home/mikpe/pkgs/linux-x86/cross-m68k/m68k-unknown-linux/lib/ -isystem
/home/mikpe/pkgs/linux-x86/cross-m68k/m68k-unknown-linux/include -isystem
/home/mikpe/pkgs/linux-x86/cross-m68k/m68k-unknown-linux/sys-include -c -g
-O2 -W -Wall -gnatpg -nostdinc a-assert.adb -o a-assert.o
+===========================GNAT BUG DETECTED==============================+
| 4.7.0 20111203 (experimental) (m68k-unknown-linux) GCC error: |
| in fp_size_to_prec, at ada/gcc-interface/misc.c:781 |
(you don't need the m68k-linux Ada support patch for this, vanilla upstream gcc
sources suffice)
This worked up to r177136, but broke due to r177137+177141.
Eric Botcazou commented:
> No, but the new code (cstand.adb:Register_Float_Type) makes an invalid
> assumption about the size of a FP mode given its precision and alignment,
> instead of using the proper interface. enumerate_modes should probably pass
> GET_MODE_BITSIZE to its callback. I'd suggest opening a new regression PR for
> this problem.
