math.h support gone from nighlty build

[jtouch]

Hi, all,

Support for math.h functions appears to have disappeared. Previous builds supported sin(), cos(), etc., and known constants.

I haven't checked nightly builds every night, but it worked in the nightly a few weeks ago (and works fine in 1.5.6-r2 and 1.5.7, but doesn't in the current nightly.

Joe

[cmaglie]

@jtouch
just checked with the current ide-1.5.x branch and it seems to work.
May you post a test sketch? Which board you selected?

[jtouch]

The board is a Due. I can't post the full code (it's proprietary), but I can post a test I wrote that also fails:

// it doesn't matter whether the following line is included or not:
// #include <math.h> 

void setup() {
  // initialize serial:
  Serial.begin(9600);
}

float a = 1.2;
float b = 0.96;

void loop() {
  float x, y;
  x = pow(10.0, a);
  y = (2.0 * acos(sqrt(b)) / M_PI);

  Serial.print(x + y);
  Serial.println();
}

Here are the errors:

mathtest.cpp.o: In function loop': C:\Users\touch\Desktop\arduino-nightly/mathtest.ino:14: warning: undefined reference topow'
C:\Users\touch\Desktop\arduino-nightly/mathtest.ino:15: warning: undefined reference to sqrt' C:\Users\touch\Desktop\arduino-nightly/mathtest.ino:15: warning: undefined reference toacos'

[cmaglie]

I see it now, it's probably a regression after this commit: 37ee800

May you try to change the recipe.c.combine.pattern definition line in your sam/platform.txt file with the following:

recipe.c.combine.pattern="{compiler.path}{compiler.c.elf.cmd}" {compiler.c.elf.flags} -mcpu={build.mcu} "-T{build.variant.path}/{build.ldscript}" "-Wl,-Map,{build.path}/{build.project_name}.map" {compiler.c.elf.extra_flags} -o "{build.path}/{build.project_name}.elf" "-L{build.path}" -mthumb -Wl,--cref -Wl,--check-sections -Wl,--gc-sections -Wl,--entry=Reset_Handler -Wl,--unresolved-symbols=report-all -Wl,--warn-common -Wl,--warn-section-align -Wl,--warn-unresolved-symbols -Wl,--start-group "{build.path}/syscalls_sam3.c.o" {object_files} "{build.variant.path}/{build.variant_system_lib}" "{build.path}/{archive_file}" -Wl,--end-group -lm -gcc

I moved the -lm -lgcc flags at the end of the command.

[matthijskooijman]

@cmaglie, huh? In the commit you referenced, you didn't touch the -lm option at all? However, you did switch from g++ to gcc, do you think that command is more picky about the ordering of link options? It seems the avr version does have -lm at the end (and has had so for as long as I can quickly see).

[cmaglie]

From my experience the command line order does matter.

I didn't checked directly but 37ee800 seems the only recent commit touching the platform.txt file and, yeah, I don't know why it was working with g++ and not with gcc.

[cmaglie]

Fix pushed for 1.5.8 and next nightly.

21939e6

@jtouch if this doesn't work for you please reopen the issue.

[jtouch]

It works. Thanks!