Invalid GCC Inline?

Alboin · Post by **Alboin** » Sat Jun 07, 2008 7:40 pm

In the wiki, there is code such as:

asm ("lidt (%0)": :"p" (&IDTR));

However, has anyone noticed that with -O2 optimizations (gcc-4.1.2), it yields:

 error: invalid 'asm': invalid expression as operand

Should we make note of this on the wiki? Fix?

Brynet-Inc · Post by **Brynet-Inc** » Sat Jun 07, 2008 8:19 pm

My solution?

-asm ("lidt (%0)": :"p" (&IDTR));
+asm ("lidt (%0)": :"r" (&IDTR));

Just an idea, seems to work with optimizations..

thepowersgang · Post by **thepowersgang** » Sat Jun 21, 2008 12:01 am

I normally use __asm__ __volatile__ (...) for inline asm. It may be that -O2 removes the use of asm(...)

lukem95 · Post by **lukem95** » Sat Jun 21, 2008 9:00 am

it depends on your compiler i think, DJGPP uses __asm__ __volatile__ ...

suthers · Post by **suthers** » Tue Jun 24, 2008 5:17 pm

lukem95 wrote:it depends on your compiler i think, DJGPP uses __asm__ __volatile__ ...

So does gcc...
Jules

Brynet-Inc · Post by **Brynet-Inc** » Tue Jun 24, 2008 10:21 pm

DJGPP == GCC for DOS.

suthers · Post by **suthers** » Wed Jun 25, 2008 5:29 am

Brynet-Inc wrote:DJGPP == GCC for DOS.

Sorry didn't know that (never used DJGPP...)

Jules

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