digitalmars.D.bugs - [Issue 5922] New: immutable and static variables usage in asm{}
- d-bugmail puremagic.com (47/47) May 03 2011 http://d.puremagic.com/issues/show_bug.cgi?id=5922
- d-bugmail puremagic.com (29/29) Mar 02 2012 http://d.puremagic.com/issues/show_bug.cgi?id=5922
- d-bugmail puremagic.com (11/11) Jan 16 2013 http://d.puremagic.com/issues/show_bug.cgi?id=5922
http://d.puremagic.com/issues/show_bug.cgi?id=5922 Summary: immutable and static variables usage in asm{} Product: D Version: D2 Platform: x86 OS/Version: Windows Status: NEW Severity: normal Priority: P2 Component: DMD AssignedTo: nobody puremagic.com ReportedBy: bearophile_hugs eml.cc I am not sure about the errors shown here (so no keywords). Please close this bug report if things here are working as expected. D2 code: void main() { immutable size_t x = 10; asm { mov EDI, x; } } DMD 2.052 shows the error: test.d(2): Error: Integer constant expression expected instead of x = 10u -------------------------- D2 code, static (thread-local) variables can't be used in ASM: void main() { static size_t x = 10; asm { mov EDI, x; } } It produces: object.Error: Access Violation They work using __gshared, this gives no errors: void main() { __gshared static size_t x = 10; asm { mov EDI, x; } } My suggestion is to remove this source of errors. One solution may be to disallow the direct access to static variables from asm code, avoiding this bug. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
May 03 2011
http://d.puremagic.com/issues/show_bug.cgi?id=5922 Denis <verylonglogin.reg gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |verylonglogin.reg gmail.com --- The first one is definetly a bug with const/immutable local variables: --- void f() { const size_t a = 1; // Error: Integer constant expression expected instead of a = 1u version (D_InlineAsm_X86_64) asm { mov RAX, a; } else version (D_InlineAsm_X86) asm { mov EAX, a; } else static assert(1); } --- The second one looks like expected behaviour because with current inline assembler for non-stack varable `someVar` instruction `mov EAX, someVar;` is equal to `mov EAX, [someVar];` and `mov EAX, [n];` where `n` is a displacement of `someVar` from some initial addres which depends on `someVar` type (global, shared, or TLS). Inline assembler behaves in this way but I've never seen any documentation and reasons *why* does it behave this way because it's really unobvious. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Mar 02 2012
http://d.puremagic.com/issues/show_bug.cgi?id=5922 yebblies <yebblies gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |yebblies gmail.com For some reason x's initializer is "x = 10" instead of just "10". Probably a side effect of some hack. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Jan 16 2013