AdaCore / AdaCore/libadalang-tools

unchecked conversion have different sizes on linux - arm64 - libadalang-tools-25.0.0 and gcc-14

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Dominant language
Ada
Stars
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Forks
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PR merge metrics
No merged PRs in 30d

Description

I got the following warnings while building:

tgen-marshalling_lib.adb:741:19: warning: types for unchecked conversion have different sizes [-gnatwz]
tgen-marshalling_lib.adb:741:19: warning: size of "Long_Long_Float" is 64, size of "Unsigned_128" is 128 [-gnatwz]
tgen-marshalling_lib.adb:741:19: warning: target value will include 64 undefined high order bits [-gnatwz]
tgen-marshalling_lib.adb:846:19: warning: types for unchecked conversion have different sizes [-gnatwz]
tgen-marshalling_lib.adb:846:19: warning: size of "Unsigned_128" is 128, size of "Long_Long_Float" is 64 [-gnatwz]
tgen-marshalling_lib.adb:846:19: warning: 64 high order bits of source will be ignored [-gnatwz]

tgen-random.adb:431:04: warning: types for unchecked conversion have different sizes [-gnatwz]
tgen-random.adb:431:04: warning: size of "Long_Long_Float" is 64, size of "Unsigned_128" is 128 [-gnatwz]
tgen-random.adb:431:04: warning: target value will include 64 undefined high order bits [-gnatwz]
tgen-random.adb:434:04: warning: types for unchecked conversion have different sizes [-gnatwz]
tgen-random.adb:434:04: warning: size of "Unsigned_128" is 128, size of "Long_Long_Float" is 64 [-gnatwz]
tgen-random.adb:434:04: warning: 64 high order bits of source will be ignored [-gnatwz]

The build stop after that

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Research direction

Reproduce the Linux arm64 build with GCC 14 and inspect the unchecked conversions at tgen-marshalling_lib.adb:741 and :846, and tgen-random.adb:431 and :434. Trace why Long_Long_Float and Unsigned_128 have different sizes, then verify that the build completes without these conversion warnings stopping it.

Written by the indexing model from the issue text.

Assessment

Tech stack
linux
Domain
build-system, compilers
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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