Bug 41185

Summary:	lround func call missing definition under MSVC leads to always zero returns
Product:	cairo	Reporter:	fmot.fics
Component:	win32 backend	Assignee:	cairo-bugs mailing list <cairo-bugs>
Status:	RESOLVED MOVED	QA Contact:	cairo-bugs mailing list <cairo-bugs>
Severity:	normal
Priority:	medium
Version:	1.10.2
Hardware:	x86 (IA32)
OS:	Windows (All)
Whiteboard:
i915 platform:		i915 features:

Description fmot.fics 2011-09-25 08:20:23 UTC

There is a piece of code in cairoint.h:
#if DISABLE_SOME_FLOATING_POINT
cairo_private int
_cairo_lround (double d) cairo_const;
#else
#define _cairo_lround lround
#endif

This code works well if lround defitionion was met before. However if cairo is compiler using MSVC there is no lround definition.
And argument is passed as int. Return from lround is thus unpredictable, but most probably zero.

I'd suggest a simple following workaround:
#if DISABLE_SOME_FLOATING_POINT
cairo_private int
_cairo_lround (double d) cairo_const;
#else
#ifdef _MSC_VER
long int lround(double x);
#endif
#define _cairo_lround lround
#endif

The bug is difficult to find. The code compiles well, does not crash but text is not printed.

Comment 1 GitLab Migration User 2018-08-25 13:42:47 UTC

-- GitLab Migration Automatic Message --

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