qualify isnan() with std namespace #565
Open
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
When a program that depends on implot includes <implot.h>, we have this sequence of includes: <implot.h> -> <implot_internal.h> -> <imgui_internal.h> -> <math.h> Inside <implot_internal.h>'s source code, there's an unqualified call to isnan(). By doing so, it relies on <imgui_internal.h> having isnan() in the global namespace, which <math.h> is guaranteed to do. However, it's possible that implot's user included <cmath> first, which is not guaranteed to put isnan() in the global namespace, and may prevent a later <math.h> from putting isnan() in the global namespace. On NetBSD 10.0 i386, <cmath> doesn't put isnan() in the global namespace and prevents <math.h> from doing so, causing a compile error. Qualify the call to fix it.
guijan
added a commit
to guijan/dolphin
that referenced
this pull request
Apr 22, 2024
The NetBSD port will only work after epezent/implot#565 is merged and Dolphin updates to a version with the fix. In the meantime, you can apply the fix yourself to a Dolphin checkout.
guijan
added a commit
to guijan/dolphin
that referenced
this pull request
Apr 22, 2024
The NetBSD port will only work after epezent/implot#565 is merged and Dolphin updates to a version with the fix. In the meantime, you can apply the fix yourself to a Dolphin checkout.
Collaborator
|
@guijan is this still an issue with the latest ImGui? I thought |
brenocq
added
type:fix
|
I can confirm that this still happens with master. I just came across this issue while trying to cross-compile from x64 to ARM64 on Linux while using glibc in particular. |
Collaborator
|
Oh... I've moved the issue to high priority :) Are you able to reproduce the issue by modifying the |
|
I've narrowed it down quite a lot, so much so that I can place the reproduction program here: #include <cmath>
#include "implot.h"
#include "implot_internal.h"
int main() { return 0; }Here is what happens when I try to compile this program using glibc and gcc/g++ from x64 to ARM64: Log OutputIt seems including cmath before implot_internal.h causes the issue to show up. This issue does not happen when compiling without a sysroot and cross-compiler, though. |
JoshuaVandaele
added a commit
to JoshuaVandaele/dolphin
that referenced
this pull request
Dec 9, 2025
JoshuaVandaele
added a commit
to JoshuaVandaele/dolphin
that referenced
this pull request
Dec 9, 2025
JoshuaVandaele
added a commit
to JoshuaVandaele/dolphin
that referenced
this pull request
Dec 9, 2025
JoshuaVandaele
added a commit
to JoshuaVandaele/dolphin
that referenced
this pull request
Dec 9, 2025
brenocq
requested changes
Dec 21, 2025
| static inline int ImPosMod(int l, int r) { return (l % r + r) % r; } | ||
| // Returns true if val is NAN | ||
| static inline bool ImNan(double val) { return isnan(val); } | ||
| static inline bool ImNan(double val) { return std::isnan(val); } |
Collaborator
There was a problem hiding this comment.
Looks like this problem is compiler-specific. Can you change it to the below? Then we can merge it.
Suggested change
| static inline bool ImNan(double val) { return std::isnan(val); } | |
| static inline bool ImNan(double val) { return (val != val); } |
There was a problem hiding this comment.
return (val != val);? Doesn't this always evaluates to false?
Collaborator
Yep, that looks pretty narrow to me... |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
5 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
See the commit message for details. I've tested this change on NetBSD only.
Found while porting dolphin-emu/dolphin to NetBSD: